Virtual hosting schema and logic changes (#2876)

Note that virtual users cannot federate correctly yet.

42 files changed, 1108 insertions, 654 deletions

diff --git a/userapi/api/api.go b/userapi/api/api.go
index 8d7f783d..d3f5aefc 100644
--- a/userapi/api/api.go
+++ b/userapi/api/api.go
@@ -78,7 +78,7 @@ type ClientUserAPI interface {
 	QueryAcccessTokenAPI
 	LoginTokenInternalAPI
 	UserLoginAPI
-	QueryNumericLocalpart(ctx context.Context, res *QueryNumericLocalpartResponse) error
+	QueryNumericLocalpart(ctx context.Context, req *QueryNumericLocalpartRequest, res *QueryNumericLocalpartResponse) error
 	QueryDevices(ctx context.Context, req *QueryDevicesRequest, res *QueryDevicesResponse) error
 	QueryProfile(ctx context.Context, req *QueryProfileRequest, res *QueryProfileResponse) error
 	QueryAccountData(ctx context.Context, req *QueryAccountDataRequest, res *QueryAccountDataResponse) error
@@ -335,9 +335,10 @@ type PerformAccountCreationResponse struct {
 
 // PerformAccountCreationRequest is the request for PerformAccountCreation
 type PerformPasswordUpdateRequest struct {
-	Localpart     string // Required: The localpart for this account.
-	Password      string // Required: The new password to set.
-	LogoutDevices bool   // Optional: Whether to log out all user devices.
+	Localpart     string                       // Required: The localpart for this account.
+	ServerName    gomatrixserverlib.ServerName // Required: The domain for this account.
+	Password      string                       // Required: The new password to set.
+	LogoutDevices bool                         // Optional: Whether to log out all user devices.
 }
 
 // PerformAccountCreationResponse is the response for PerformAccountCreation
@@ -518,7 +519,8 @@ const (
 )
 
 type QueryPushersRequest struct {
-	Localpart string
+	Localpart  string
+	ServerName gomatrixserverlib.ServerName
 }
 
 type QueryPushersResponse struct {
@@ -526,14 +528,16 @@ type QueryPushersResponse struct {
 }
 
 type PerformPusherSetRequest struct {
-	Pusher    // Anonymous field because that's how clientapi unmarshals it.
-	Localpart string
-	Append    bool `json:"append"`
+	Pusher     // Anonymous field because that's how clientapi unmarshals it.
+	Localpart  string
+	ServerName gomatrixserverlib.ServerName
+	Append     bool `json:"append"`
 }
 
 type PerformPusherDeletionRequest struct {
-	Localpart string
-	SessionID int64
+	Localpart  string
+	ServerName gomatrixserverlib.ServerName
+	SessionID  int64
 }
 
 // Pusher represents a push notification subscriber
@@ -571,10 +575,11 @@ type QueryPushRulesResponse struct {
 }
 
 type QueryNotificationsRequest struct {
-	Localpart string `json:"localpart"` // Required.
-	From      string `json:"from,omitempty"`
-	Limit     int    `json:"limit,omitempty"`
-	Only      string `json:"only,omitempty"`
+	Localpart  string                       `json:"localpart"`   // Required.
+	ServerName gomatrixserverlib.ServerName `json:"server_name"` // Required.
+	From       string                       `json:"from,omitempty"`
+	Limit      int                          `json:"limit,omitempty"`
+	Only       string                       `json:"only,omitempty"`
 }
 
 type QueryNotificationsResponse struct {
@@ -601,12 +606,17 @@ type PerformSetAvatarURLResponse struct {
 	Changed bool               `json:"changed"`
 }
 
+type QueryNumericLocalpartRequest struct {
+	ServerName gomatrixserverlib.ServerName
+}
+
 type QueryNumericLocalpartResponse struct {
 	ID int64
 }
 
 type QueryAccountAvailabilityRequest struct {
-	Localpart string
+	Localpart  string
+	ServerName gomatrixserverlib.ServerName
 }
 
 type QueryAccountAvailabilityResponse struct {
@@ -614,7 +624,9 @@ type QueryAccountAvailabilityResponse struct {
 }
 
 type QueryAccountByPasswordRequest struct {
-	Localpart, PlaintextPassword string
+	Localpart         string
+	ServerName        gomatrixserverlib.ServerName
+	PlaintextPassword string
 }
 
 type QueryAccountByPasswordResponse struct {
@@ -638,11 +650,13 @@ type QueryLocalpartForThreePIDRequest struct {
 }
 
 type QueryLocalpartForThreePIDResponse struct {
-	Localpart string
+	Localpart  string
+	ServerName gomatrixserverlib.ServerName
 }
 
 type QueryThreePIDsForLocalpartRequest struct {
-	Localpart string
+	Localpart  string
+	ServerName gomatrixserverlib.ServerName
 }
 
 type QueryThreePIDsForLocalpartResponse struct {
@@ -652,5 +666,8 @@ type QueryThreePIDsForLocalpartResponse struct {
 type PerformForgetThreePIDRequest QueryLocalpartForThreePIDRequest
 
 type PerformSaveThreePIDAssociationRequest struct {
-	ThreePID, Localpart, Medium string
+	ThreePID   string
+	Localpart  string
+	ServerName gomatrixserverlib.ServerName
+	Medium     string
 }
diff --git a/userapi/api/api_trace.go b/userapi/api/api_trace.go
index 90834f7e..ce661770 100644
--- a/userapi/api/api_trace.go
+++ b/userapi/api/api_trace.go
@@ -156,8 +156,8 @@ func (t *UserInternalAPITrace) SetAvatarURL(ctx context.Context, req *PerformSet
 	return err
 }
 
-func (t *UserInternalAPITrace) QueryNumericLocalpart(ctx context.Context, res *QueryNumericLocalpartResponse) error {
-	err := t.Impl.QueryNumericLocalpart(ctx, res)
+func (t *UserInternalAPITrace) QueryNumericLocalpart(ctx context.Context, req *QueryNumericLocalpartRequest, res *QueryNumericLocalpartResponse) error {
+	err := t.Impl.QueryNumericLocalpart(ctx, req, res)
 	util.GetLogger(ctx).Infof("QueryNumericLocalpart req= res=%+v", js(res))
 	return err
 }
diff --git a/userapi/consumers/clientapi.go b/userapi/consumers/clientapi.go
index 79f1bf06..42ae72e7 100644
--- a/userapi/consumers/clientapi.go
+++ b/userapi/consumers/clientapi.go
@@ -104,7 +104,7 @@ func (s *OutputReceiptEventConsumer) onMessage(ctx context.Context, msgs []*nats
 		return false
 	}
 
-	updated, err := s.db.SetNotificationsRead(ctx, localpart, roomID, uint64(gomatrixserverlib.AsTimestamp(metadata.Timestamp)), true)
+	updated, err := s.db.SetNotificationsRead(ctx, localpart, domain, roomID, uint64(gomatrixserverlib.AsTimestamp(metadata.Timestamp)), true)
 	if err != nil {
 		log.WithError(err).Error("userapi EDU consumer")
 		return false
@@ -118,7 +118,7 @@ func (s *OutputReceiptEventConsumer) onMessage(ctx context.Context, msgs []*nats
 	if !updated {
 		return true
 	}
-	if err = util.NotifyUserCountsAsync(ctx, s.pgClient, localpart, s.db); err != nil {
+	if err = util.NotifyUserCountsAsync(ctx, s.pgClient, localpart, domain, s.db); err != nil {
 		log.WithError(err).Error("userapi EDU consumer: NotifyUserCounts failed")
 		return false
 	}
diff --git a/userapi/consumers/roomserver.go b/userapi/consumers/roomserver.go
index b6b30a09..5d8924dd 100644
--- a/userapi/consumers/roomserver.go
+++ b/userapi/consumers/roomserver.go
@@ -192,25 +192,25 @@ func (s *OutputRoomEventConsumer) storeMessageStats(ctx context.Context, eventTy
 func (s *OutputRoomEventConsumer) handleRoomUpgrade(ctx context.Context, oldRoomID, newRoomID string, localMembers []*localMembership, roomSize int) error {
 	for _, membership := range localMembers {
 		// Copy any existing push rules from old -> new room
-		if err := s.copyPushrules(ctx, oldRoomID, newRoomID, membership.Localpart); err != nil {
+		if err := s.copyPushrules(ctx, oldRoomID, newRoomID, membership.Localpart, membership.Domain); err != nil {
 			return err
 		}
 
 		// preserve m.direct room state
-		if err := s.updateMDirect(ctx, oldRoomID, newRoomID, membership.Localpart, roomSize); err != nil {
+		if err := s.updateMDirect(ctx, oldRoomID, newRoomID, membership.Localpart, membership.Domain, roomSize); err != nil {
 			return err
 		}
 
 		// copy existing m.tag entries, if any
-		if err := s.copyTags(ctx, oldRoomID, newRoomID, membership.Localpart); err != nil {
+		if err := s.copyTags(ctx, oldRoomID, newRoomID, membership.Localpart, membership.Domain); err != nil {
 			return err
 		}
 	}
 	return nil
 }
 
-func (s *OutputRoomEventConsumer) copyPushrules(ctx context.Context, oldRoomID, newRoomID string, localpart string) error {
-	pushRules, err := s.db.QueryPushRules(ctx, localpart)
+func (s *OutputRoomEventConsumer) copyPushrules(ctx context.Context, oldRoomID, newRoomID string, localpart string, serverName gomatrixserverlib.ServerName) error {
+	pushRules, err := s.db.QueryPushRules(ctx, localpart, serverName)
 	if err != nil {
 		return fmt.Errorf("failed to query pushrules for user: %w", err)
 	}
@@ -229,7 +229,7 @@ func (s *OutputRoomEventConsumer) copyPushrules(ctx context.Context, oldRoomID,
 		if err != nil {
 			return err
 		}
-		if err = s.db.SaveAccountData(ctx, localpart, "", "m.push_rules", rules); err != nil {
+		if err = s.db.SaveAccountData(ctx, localpart, serverName, "", "m.push_rules", rules); err != nil {
 			return fmt.Errorf("failed to update pushrules: %w", err)
 		}
 	}
@@ -237,13 +237,13 @@ func (s *OutputRoomEventConsumer) copyPushrules(ctx context.Context, oldRoomID,
 }
 
 // updateMDirect copies the "is_direct" flag from oldRoomID to newROomID
-func (s *OutputRoomEventConsumer) updateMDirect(ctx context.Context, oldRoomID, newRoomID, localpart string, roomSize int) error {
+func (s *OutputRoomEventConsumer) updateMDirect(ctx context.Context, oldRoomID, newRoomID, localpart string, serverName gomatrixserverlib.ServerName, roomSize int) error {
 	// this is most likely not a DM, so skip updating m.direct state
 	if roomSize > 2 {
 		return nil
 	}
 	// Get direct message state
-	directChatsRaw, err := s.db.GetAccountDataByType(ctx, localpart, "", "m.direct")
+	directChatsRaw, err := s.db.GetAccountDataByType(ctx, localpart, serverName, "", "m.direct")
 	if err != nil {
 		return fmt.Errorf("failed to get m.direct from database: %w", err)
 	}
@@ -267,7 +267,7 @@ func (s *OutputRoomEventConsumer) updateMDirect(ctx context.Context, oldRoomID,
 			if err != nil {
 				return true
 			}
-			if err = s.db.SaveAccountData(ctx, localpart, "", "m.direct", data); err != nil {
+			if err = s.db.SaveAccountData(ctx, localpart, serverName, "", "m.direct", data); err != nil {
 				return true
 			}
 		}
@@ -279,15 +279,15 @@ func (s *OutputRoomEventConsumer) updateMDirect(ctx context.Context, oldRoomID,
 	return nil
 }
 
-func (s *OutputRoomEventConsumer) copyTags(ctx context.Context, oldRoomID, newRoomID, localpart string) error {
-	tag, err := s.db.GetAccountDataByType(ctx, localpart, oldRoomID, "m.tag")
+func (s *OutputRoomEventConsumer) copyTags(ctx context.Context, oldRoomID, newRoomID, localpart string, serverName gomatrixserverlib.ServerName) error {
+	tag, err := s.db.GetAccountDataByType(ctx, localpart, serverName, oldRoomID, "m.tag")
 	if err != nil && !errors.Is(err, sql.ErrNoRows) {
 		return err
 	}
 	if tag == nil {
 		return nil
 	}
-	return s.db.SaveAccountData(ctx, localpart, newRoomID, "m.tag", tag)
+	return s.db.SaveAccountData(ctx, localpart, serverName, newRoomID, "m.tag", tag)
 }
 
 func (s *OutputRoomEventConsumer) processMessage(ctx context.Context, event *gomatrixserverlib.HeaderedEvent, streamPos uint64) error {
@@ -492,11 +492,11 @@ func unmarshalCanonicalAlias(event *gomatrixserverlib.HeaderedEvent) (string, er
 func (s *OutputRoomEventConsumer) notifyLocal(ctx context.Context, event *gomatrixserverlib.HeaderedEvent, mem *localMembership, roomSize int, roomName string, streamPos uint64) error {
 	actions, err := s.evaluatePushRules(ctx, event, mem, roomSize)
 	if err != nil {
-		return err
+		return fmt.Errorf("s.evaluatePushRules: %w", err)
 	}
 	a, tweaks, err := pushrules.ActionsToTweaks(actions)
 	if err != nil {
-		return err
+		return fmt.Errorf("pushrules.ActionsToTweaks: %w", err)
 	}
 	// TODO: support coalescing.
 	if a != pushrules.NotifyAction && a != pushrules.CoalesceAction {
@@ -508,9 +508,9 @@ func (s *OutputRoomEventConsumer) notifyLocal(ctx context.Context, event *gomatr
 		return nil
 	}
 
-	devicesByURLAndFormat, profileTag, err := s.localPushDevices(ctx, mem.Localpart, tweaks)
+	devicesByURLAndFormat, profileTag, err := s.localPushDevices(ctx, mem.Localpart, mem.Domain, tweaks)
 	if err != nil {
-		return err
+		return fmt.Errorf("s.localPushDevices: %w", err)
 	}
 
 	n := &api.Notification{
@@ -527,18 +527,18 @@ func (s *OutputRoomEventConsumer) notifyLocal(ctx context.Context, event *gomatr
 		RoomID:     event.RoomID(),
 		TS:         gomatrixserverlib.AsTimestamp(time.Now()),
 	}
-	if err = s.db.InsertNotification(ctx, mem.Localpart, event.EventID(), streamPos, tweaks, n); err != nil {
-		return err
+	if err = s.db.InsertNotification(ctx, mem.Localpart, mem.Domain, event.EventID(), streamPos, tweaks, n); err != nil {
+		return fmt.Errorf("s.db.InsertNotification: %w", err)
 	}
 
 	if err = s.syncProducer.GetAndSendNotificationData(ctx, mem.UserID, event.RoomID()); err != nil {
-		return err
+		return fmt.Errorf("s.syncProducer.GetAndSendNotificationData: %w", err)
 	}
 
 	// We do this after InsertNotification. Thus, this should always return >=1.
-	userNumUnreadNotifs, err := s.db.GetNotificationCount(ctx, mem.Localpart, tables.AllNotifications)
+	userNumUnreadNotifs, err := s.db.GetNotificationCount(ctx, mem.Localpart, mem.Domain, tables.AllNotifications)
 	if err != nil {
-		return err
+		return fmt.Errorf("s.db.GetNotificationCount: %w", err)
 	}
 
 	log.WithFields(log.Fields{
@@ -589,7 +589,7 @@ func (s *OutputRoomEventConsumer) notifyLocal(ctx context.Context, event *gomatr
 		}
 
 		if len(rejected) > 0 {
-			s.deleteRejectedPushers(ctx, rejected, mem.Localpart)
+			s.deleteRejectedPushers(ctx, rejected, mem.Localpart, mem.Domain)
 		}
 	}()
 
@@ -606,7 +606,7 @@ func (s *OutputRoomEventConsumer) evaluatePushRules(ctx context.Context, event *
 	}
 
 	// Get accountdata to check if the event.Sender() is ignored by mem.LocalPart
-	data, err := s.db.GetAccountDataByType(ctx, mem.Localpart, "", "m.ignored_user_list")
+	data, err := s.db.GetAccountDataByType(ctx, mem.Localpart, mem.Domain, "", "m.ignored_user_list")
 	if err != nil {
 		return nil, err
 	}
@@ -621,7 +621,7 @@ func (s *OutputRoomEventConsumer) evaluatePushRules(ctx context.Context, event *
 			return nil, fmt.Errorf("user %s is ignored", sender)
 		}
 	}
-	ruleSets, err := s.db.QueryPushRules(ctx, mem.Localpart)
+	ruleSets, err := s.db.QueryPushRules(ctx, mem.Localpart, mem.Domain)
 	if err != nil {
 		return nil, err
 	}
@@ -693,10 +693,10 @@ func (rse *ruleSetEvalContext) HasPowerLevel(userID, levelKey string) (bool, err
 
 // localPushDevices pushes to the configured devices of a local
 // user. The map keys are [url][format].
-func (s *OutputRoomEventConsumer) localPushDevices(ctx context.Context, localpart string, tweaks map[string]interface{}) (map[string]map[string][]*pushgateway.Device, string, error) {
-	pusherDevices, err := util.GetPushDevices(ctx, localpart, tweaks, s.db)
+func (s *OutputRoomEventConsumer) localPushDevices(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, tweaks map[string]interface{}) (map[string]map[string][]*pushgateway.Device, string, error) {
+	pusherDevices, err := util.GetPushDevices(ctx, localpart, serverName, tweaks, s.db)
 	if err != nil {
-		return nil, "", err
+		return nil, "", fmt.Errorf("util.GetPushDevices: %w", err)
 	}
 
 	var profileTag string
@@ -791,7 +791,7 @@ func (s *OutputRoomEventConsumer) notifyHTTP(ctx context.Context, event *gomatri
 }
 
 // deleteRejectedPushers deletes the pushers associated with the given devices.
-func (s *OutputRoomEventConsumer) deleteRejectedPushers(ctx context.Context, devices []*pushgateway.Device, localpart string) {
+func (s *OutputRoomEventConsumer) deleteRejectedPushers(ctx context.Context, devices []*pushgateway.Device, localpart string, serverName gomatrixserverlib.ServerName) {
 	log.WithFields(log.Fields{
 		"localpart":   localpart,
 		"app_id0":     devices[0].AppID,
@@ -799,7 +799,7 @@ func (s *OutputRoomEventConsumer) deleteRejectedPushers(ctx context.Context, dev
 	}).Warnf("Deleting pushers rejected by the HTTP push gateway")
 
 	for _, d := range devices {
-		if err := s.db.RemovePusher(ctx, d.AppID, d.PushKey, localpart); err != nil {
+		if err := s.db.RemovePusher(ctx, d.AppID, d.PushKey, localpart, serverName); err != nil {
 			log.WithFields(log.Fields{
 				"localpart": localpart,
 			}).WithError(err).Errorf("Unable to delete rejected pusher")
diff --git a/userapi/internal/api.go b/userapi/internal/api.go
index 9ca76965..3f256457 100644
--- a/userapi/internal/api.go
+++ b/userapi/internal/api.go
@@ -68,7 +68,7 @@ func (a *UserInternalAPI) InputAccountData(ctx context.Context, req *api.InputAc
 	if req.DataType == "" {
 		return fmt.Errorf("data type must not be empty")
 	}
-	if err := a.DB.SaveAccountData(ctx, local, req.RoomID, req.DataType, req.AccountData); err != nil {
+	if err := a.DB.SaveAccountData(ctx, local, domain, req.RoomID, req.DataType, req.AccountData); err != nil {
 		util.GetLogger(ctx).WithError(err).Error("a.DB.SaveAccountData failed")
 		return fmt.Errorf("failed to save account data: %w", err)
 	}
@@ -108,7 +108,7 @@ func (a *UserInternalAPI) setFullyRead(ctx context.Context, req *api.InputAccoun
 		return nil
 	}
 
-	deleted, err := a.DB.DeleteNotificationsUpTo(ctx, localpart, req.RoomID, uint64(gomatrixserverlib.AsTimestamp(time.Now())))
+	deleted, err := a.DB.DeleteNotificationsUpTo(ctx, localpart, domain, req.RoomID, uint64(gomatrixserverlib.AsTimestamp(time.Now())))
 	if err != nil {
 		logrus.WithError(err).Errorf("UserInternalAPI.setFullyRead: DeleteNotificationsUpTo failed")
 		return err
@@ -124,7 +124,7 @@ func (a *UserInternalAPI) setFullyRead(ctx context.Context, req *api.InputAccoun
 		return nil
 	}
 
-	if err = userapiUtil.NotifyUserCountsAsync(ctx, a.PgClient, localpart, a.DB); err != nil {
+	if err = userapiUtil.NotifyUserCountsAsync(ctx, a.PgClient, localpart, domain, a.DB); err != nil {
 		logrus.WithError(err).Error("UserInternalAPI.setFullyRead: NotifyUserCounts failed")
 		return err
 	}
@@ -175,8 +175,10 @@ func (a *UserInternalAPI) PerformAccountCreation(ctx context.Context, req *api.P
 	if serverName == "" {
 		serverName = a.Config.Matrix.ServerName
 	}
-	// XXXX: Use the server name here
-	acc, err := a.DB.CreateAccount(ctx, req.Localpart, req.Password, req.AppServiceID, req.AccountType)
+	if !a.Config.Matrix.IsLocalServerName(serverName) {
+		return fmt.Errorf("server name %s is not local", serverName)
+	}
+	acc, err := a.DB.CreateAccount(ctx, req.Localpart, serverName, req.Password, req.AppServiceID, req.AccountType)
 	if err != nil {
 		if errors.Is(err, sqlutil.ErrUserExists) { // This account already exists
 			switch req.OnConflict {
@@ -215,8 +217,8 @@ func (a *UserInternalAPI) PerformAccountCreation(ctx context.Context, req *api.P
 		return nil
 	}
 
-	if _, _, err = a.DB.SetDisplayName(ctx, req.Localpart, req.Localpart); err != nil {
-		return err
+	if _, _, err = a.DB.SetDisplayName(ctx, req.Localpart, serverName, req.Localpart); err != nil {
+		return fmt.Errorf("a.DB.SetDisplayName: %w", err)
 	}
 
 	postRegisterJoinRooms(a.Cfg, acc, a.RSAPI)
@@ -227,11 +229,14 @@ func (a *UserInternalAPI) PerformAccountCreation(ctx context.Context, req *api.P
 }
 
 func (a *UserInternalAPI) PerformPasswordUpdate(ctx context.Context, req *api.PerformPasswordUpdateRequest, res *api.PerformPasswordUpdateResponse) error {
-	if err := a.DB.SetPassword(ctx, req.Localpart, req.Password); err != nil {
+	if !a.Config.Matrix.IsLocalServerName(req.ServerName) {
+		return fmt.Errorf("server name %s is not local", req.ServerName)
+	}
+	if err := a.DB.SetPassword(ctx, req.Localpart, req.ServerName, req.Password); err != nil {
 		return err
 	}
 	if req.LogoutDevices {
-		if _, err := a.DB.RemoveAllDevices(context.Background(), req.Localpart, ""); err != nil {
+		if _, err := a.DB.RemoveAllDevices(context.Background(), req.Localpart, req.ServerName, ""); err != nil {
 			return err
 		}
 	}
@@ -244,14 +249,15 @@ func (a *UserInternalAPI) PerformDeviceCreation(ctx context.Context, req *api.Pe
 	if serverName == "" {
 		serverName = a.Config.Matrix.ServerName
 	}
-	_ = serverName
-	// XXXX: Use the server name here
+	if !a.Config.Matrix.IsLocalServerName(serverName) {
+		return fmt.Errorf("server name %s is not local", serverName)
+	}
 	util.GetLogger(ctx).WithFields(logrus.Fields{
 		"localpart":    req.Localpart,
 		"device_id":    req.DeviceID,
 		"display_name": req.DeviceDisplayName,
 	}).Info("PerformDeviceCreation")
-	dev, err := a.DB.CreateDevice(ctx, req.Localpart, req.DeviceID, req.AccessToken, req.DeviceDisplayName, req.IPAddr, req.UserAgent)
+	dev, err := a.DB.CreateDevice(ctx, req.Localpart, serverName, req.DeviceID, req.AccessToken, req.DeviceDisplayName, req.IPAddr, req.UserAgent)
 	if err != nil {
 		return err
 	}
@@ -276,12 +282,12 @@ func (a *UserInternalAPI) PerformDeviceDeletion(ctx context.Context, req *api.Pe
 	deletedDeviceIDs := req.DeviceIDs
 	if len(req.DeviceIDs) == 0 {
 		var devices []api.Device
-		devices, err = a.DB.RemoveAllDevices(ctx, local, req.ExceptDeviceID)
+		devices, err = a.DB.RemoveAllDevices(ctx, local, domain, req.ExceptDeviceID)
 		for _, d := range devices {
 			deletedDeviceIDs = append(deletedDeviceIDs, d.ID)
 		}
 	} else {
-		err = a.DB.RemoveDevices(ctx, local, req.DeviceIDs)
+		err = a.DB.RemoveDevices(ctx, local, domain, req.DeviceIDs)
 	}
 	if err != nil {
 		return err
@@ -335,23 +341,29 @@ func (a *UserInternalAPI) PerformLastSeenUpdate(
 	req *api.PerformLastSeenUpdateRequest,
 	res *api.PerformLastSeenUpdateResponse,
 ) error {
-	localpart, _, err := gomatrixserverlib.SplitID('@', req.UserID)
+	localpart, domain, err := gomatrixserverlib.SplitID('@', req.UserID)
 	if err != nil {
 		return fmt.Errorf("gomatrixserverlib.SplitID: %w", err)
 	}
-	if err := a.DB.UpdateDeviceLastSeen(ctx, localpart, req.DeviceID, req.RemoteAddr, req.UserAgent); err != nil {
+	if !a.Config.Matrix.IsLocalServerName(domain) {
+		return fmt.Errorf("server name %s is not local", domain)
+	}
+	if err := a.DB.UpdateDeviceLastSeen(ctx, localpart, domain, req.DeviceID, req.RemoteAddr, req.UserAgent); err != nil {
 		return fmt.Errorf("a.DeviceDB.UpdateDeviceLastSeen: %w", err)
 	}
 	return nil
 }
 
 func (a *UserInternalAPI) PerformDeviceUpdate(ctx context.Context, req *api.PerformDeviceUpdateRequest, res *api.PerformDeviceUpdateResponse) error {
-	localpart, _, err := gomatrixserverlib.SplitID('@', req.RequestingUserID)
+	localpart, domain, err := gomatrixserverlib.SplitID('@', req.RequestingUserID)
 	if err != nil {
 		util.GetLogger(ctx).WithError(err).Error("gomatrixserverlib.SplitID failed")
 		return err
 	}
-	dev, err := a.DB.GetDeviceByID(ctx, localpart, req.DeviceID)
+	if !a.Config.Matrix.IsLocalServerName(domain) {
+		return fmt.Errorf("server name %s is not local", domain)
+	}
+	dev, err := a.DB.GetDeviceByID(ctx, localpart, domain, req.DeviceID)
 	if err == sql.ErrNoRows {
 		res.DeviceExists = false
 		return nil
@@ -366,7 +378,7 @@ func (a *UserInternalAPI) PerformDeviceUpdate(ctx context.Context, req *api.Perf
 		return nil
 	}
 
-	err = a.DB.UpdateDevice(ctx, localpart, req.DeviceID, req.DisplayName)
+	err = a.DB.UpdateDevice(ctx, localpart, domain, req.DeviceID, req.DisplayName)
 	if err != nil {
 		util.GetLogger(ctx).WithError(err).Error("deviceDB.UpdateDevice failed")
 		return err
@@ -406,7 +418,7 @@ func (a *UserInternalAPI) QueryProfile(ctx context.Context, req *api.QueryProfil
 	if !a.Config.Matrix.IsLocalServerName(domain) {
 		return fmt.Errorf("cannot query profile of remote users (server name %s)", domain)
 	}
-	prof, err := a.DB.GetProfileByLocalpart(ctx, local)
+	prof, err := a.DB.GetProfileByLocalpart(ctx, local, domain)
 	if err != nil {
 		if err == sql.ErrNoRows {
 			return nil
@@ -457,7 +469,7 @@ func (a *UserInternalAPI) QueryDevices(ctx context.Context, req *api.QueryDevice
 	if !a.Config.Matrix.IsLocalServerName(domain) {
 		return fmt.Errorf("cannot query devices of remote users (server name %s)", domain)
 	}
-	devs, err := a.DB.GetDevicesByLocalpart(ctx, local)
+	devs, err := a.DB.GetDevicesByLocalpart(ctx, local, domain)
 	if err != nil {
 		return err
 	}
@@ -476,7 +488,7 @@ func (a *UserInternalAPI) QueryAccountData(ctx context.Context, req *api.QueryAc
 	}
 	if req.DataType != "" {
 		var data json.RawMessage
-		data, err = a.DB.GetAccountDataByType(ctx, local, req.RoomID, req.DataType)
+		data, err = a.DB.GetAccountDataByType(ctx, local, domain, req.RoomID, req.DataType)
 		if err != nil {
 			return err
 		}
@@ -494,7 +506,7 @@ func (a *UserInternalAPI) QueryAccountData(ctx context.Context, req *api.QueryAc
 		}
 		return nil
 	}
-	global, rooms, err := a.DB.GetAccountData(ctx, local)
+	global, rooms, err := a.DB.GetAccountData(ctx, local, domain)
 	if err != nil {
 		return err
 	}
@@ -527,7 +539,7 @@ func (a *UserInternalAPI) QueryAccessToken(ctx context.Context, req *api.QueryAc
 	if !a.Config.Matrix.IsLocalServerName(domain) {
 		return nil
 	}
-	acc, err := a.DB.GetAccountByLocalpart(ctx, localPart)
+	acc, err := a.DB.GetAccountByLocalpart(ctx, localPart, domain)
 	if err != nil {
 		return err
 	}
@@ -561,14 +573,14 @@ func (a *UserInternalAPI) queryAppServiceToken(ctx context.Context, token, appSe
 		AccountType:  api.AccountTypeAppService,
 	}
 
-	localpart, _, err := userutil.ParseUsernameParam(appServiceUserID, a.Config.Matrix)
+	localpart, domain, err := userutil.ParseUsernameParam(appServiceUserID, a.Config.Matrix)
 	if err != nil {
 		return nil, err
 	}
 
 	if localpart != "" { // AS is masquerading as another user
 		// Verify that the user is registered
-		account, err := a.DB.GetAccountByLocalpart(ctx, localpart)
+		account, err := a.DB.GetAccountByLocalpart(ctx, localpart, domain)
 		// Verify that the account exists and either appServiceID matches or
 		// it belongs to the appservice user namespaces
 		if err == nil && (account.AppServiceID == appService.ID || appService.IsInterestedInUserID(appServiceUserID)) {
@@ -620,7 +632,7 @@ func (a *UserInternalAPI) PerformAccountDeactivation(ctx context.Context, req *a
 		return err
 	}
 
-	err := a.DB.DeactivateAccount(ctx, req.Localpart)
+	err := a.DB.DeactivateAccount(ctx, req.Localpart, serverName)
 	res.AccountDeactivated = err == nil
 	return err
 }
@@ -783,7 +795,7 @@ func (a *UserInternalAPI) QueryNotifications(ctx context.Context, req *api.Query
 	if req.Only == "highlight" {
 		filter = tables.HighlightNotifications
 	}
-	notifs, lastID, err := a.DB.GetNotifications(ctx, req.Localpart, fromID, req.Limit, filter)
+	notifs, lastID, err := a.DB.GetNotifications(ctx, req.Localpart, req.ServerName, fromID, req.Limit, filter)
 	if err != nil {
 		return err
 	}
@@ -811,23 +823,23 @@ func (a *UserInternalAPI) PerformPusherSet(ctx context.Context, req *api.Perform
 		}
 	}
 	if req.Pusher.Kind == "" {
-		return a.DB.RemovePusher(ctx, req.Pusher.AppID, req.Pusher.PushKey, req.Localpart)
+		return a.DB.RemovePusher(ctx, req.Pusher.AppID, req.Pusher.PushKey, req.Localpart, req.ServerName)
 	}
 	if req.Pusher.PushKeyTS == 0 {
 		req.Pusher.PushKeyTS = int64(time.Now().Unix())
 	}
-	return a.DB.UpsertPusher(ctx, req.Pusher, req.Localpart)
+	return a.DB.UpsertPusher(ctx, req.Pusher, req.Localpart, req.ServerName)
 }
 
 func (a *UserInternalAPI) PerformPusherDeletion(ctx context.Context, req *api.PerformPusherDeletionRequest, res *struct{}) error {
-	pushers, err := a.DB.GetPushers(ctx, req.Localpart)
+	pushers, err := a.DB.GetPushers(ctx, req.Localpart, req.ServerName)
 	if err != nil {
 		return err
 	}
 	for i := range pushers {
 		logrus.Warnf("pusher session: %d, req session: %d", pushers[i].SessionID, req.SessionID)
 		if pushers[i].SessionID != req.SessionID {
-			err := a.DB.RemovePusher(ctx, pushers[i].AppID, pushers[i].PushKey, req.Localpart)
+			err := a.DB.RemovePusher(ctx, pushers[i].AppID, pushers[i].PushKey, req.Localpart, req.ServerName)
 			if err != nil {
 				return err
 			}
@@ -838,7 +850,7 @@ func (a *UserInternalAPI) PerformPusherDeletion(ctx context.Context, req *api.Pe
 
 func (a *UserInternalAPI) QueryPushers(ctx context.Context, req *api.QueryPushersRequest, res *api.QueryPushersResponse) error {
 	var err error
-	res.Pushers, err = a.DB.GetPushers(ctx, req.Localpart)
+	res.Pushers, err = a.DB.GetPushers(ctx, req.Localpart, req.ServerName)
 	return err
 }
 
@@ -864,11 +876,11 @@ func (a *UserInternalAPI) PerformPushRulesPut(
 }
 
 func (a *UserInternalAPI) QueryPushRules(ctx context.Context, req *api.QueryPushRulesRequest, res *api.QueryPushRulesResponse) error {
-	localpart, _, err := gomatrixserverlib.SplitID('@', req.UserID)
+	localpart, domain, err := gomatrixserverlib.SplitID('@', req.UserID)
 	if err != nil {
 		return fmt.Errorf("failed to split user ID %q for push rules", req.UserID)
 	}
-	pushRules, err := a.DB.QueryPushRules(ctx, localpart)
+	pushRules, err := a.DB.QueryPushRules(ctx, localpart, domain)
 	if err != nil {
 		return fmt.Errorf("failed to query push rules: %w", err)
 	}
@@ -877,14 +889,14 @@ func (a *UserInternalAPI) QueryPushRules(ctx context.Context, req *api.QueryPush
 }
 
 func (a *UserInternalAPI) SetAvatarURL(ctx context.Context, req *api.PerformSetAvatarURLRequest, res *api.PerformSetAvatarURLResponse) error {
-	profile, changed, err := a.DB.SetAvatarURL(ctx, req.Localpart, req.AvatarURL)
+	profile, changed, err := a.DB.SetAvatarURL(ctx, req.Localpart, req.ServerName, req.AvatarURL)
 	res.Profile = profile
 	res.Changed = changed
 	return err
 }
 
-func (a *UserInternalAPI) QueryNumericLocalpart(ctx context.Context, res *api.QueryNumericLocalpartResponse) error {
-	id, err := a.DB.GetNewNumericLocalpart(ctx)
+func (a *UserInternalAPI) QueryNumericLocalpart(ctx context.Context, req *api.QueryNumericLocalpartRequest, res *api.QueryNumericLocalpartResponse) error {
+	id, err := a.DB.GetNewNumericLocalpart(ctx, req.ServerName)
 	if err != nil {
 		return err
 	}
@@ -894,12 +906,12 @@ func (a *UserInternalAPI) QueryNumericLocalpart(ctx context.Context, res *api.Qu
 
 func (a *UserInternalAPI) QueryAccountAvailability(ctx context.Context, req *api.QueryAccountAvailabilityRequest, res *api.QueryAccountAvailabilityResponse) error {
 	var err error
-	res.Available, err = a.DB.CheckAccountAvailability(ctx, req.Localpart)
+	res.Available, err = a.DB.CheckAccountAvailability(ctx, req.Localpart, req.ServerName)
 	return err
 }
 
 func (a *UserInternalAPI) QueryAccountByPassword(ctx context.Context, req *api.QueryAccountByPasswordRequest, res *api.QueryAccountByPasswordResponse) error {
-	acc, err := a.DB.GetAccountByPassword(ctx, req.Localpart, req.PlaintextPassword)
+	acc, err := a.DB.GetAccountByPassword(ctx, req.Localpart, req.ServerName, req.PlaintextPassword)
 	switch err {
 	case sql.ErrNoRows: // user does not exist
 		return nil
@@ -915,23 +927,24 @@ func (a *UserInternalAPI) QueryAccountByPassword(ctx context.Context, req *api.Q
 }
 
 func (a *UserInternalAPI) SetDisplayName(ctx context.Context, req *api.PerformUpdateDisplayNameRequest, res *api.PerformUpdateDisplayNameResponse) error {
-	profile, changed, err := a.DB.SetDisplayName(ctx, req.Localpart, req.DisplayName)
+	profile, changed, err := a.DB.SetDisplayName(ctx, req.Localpart, req.ServerName, req.DisplayName)
 	res.Profile = profile
 	res.Changed = changed
 	return err
 }
 
 func (a *UserInternalAPI) QueryLocalpartForThreePID(ctx context.Context, req *api.QueryLocalpartForThreePIDRequest, res *api.QueryLocalpartForThreePIDResponse) error {
-	localpart, err := a.DB.GetLocalpartForThreePID(ctx, req.ThreePID, req.Medium)
+	localpart, domain, err := a.DB.GetLocalpartForThreePID(ctx, req.ThreePID, req.Medium)
 	if err != nil {
 		return err
 	}
 	res.Localpart = localpart
+	res.ServerName = domain
 	return nil
 }
 
 func (a *UserInternalAPI) QueryThreePIDsForLocalpart(ctx context.Context, req *api.QueryThreePIDsForLocalpartRequest, res *api.QueryThreePIDsForLocalpartResponse) error {
-	r, err := a.DB.GetThreePIDsForLocalpart(ctx, req.Localpart)
+	r, err := a.DB.GetThreePIDsForLocalpart(ctx, req.Localpart, req.ServerName)
 	if err != nil {
 		return err
 	}
@@ -944,7 +957,7 @@ func (a *UserInternalAPI) PerformForgetThreePID(ctx context.Context, req *api.Pe
 }
 
 func (a *UserInternalAPI) PerformSaveThreePIDAssociation(ctx context.Context, req *api.PerformSaveThreePIDAssociationRequest, res *struct{}) error {
-	return a.DB.SaveThreePIDAssociation(ctx, req.ThreePID, req.Localpart, req.Medium)
+	return a.DB.SaveThreePIDAssociation(ctx, req.ThreePID, req.Localpart, req.ServerName, req.Medium)
 }
 
 const pushRulesAccountDataType = "m.push_rules"
diff --git a/userapi/internal/api_logintoken.go b/userapi/internal/api_logintoken.go
index 87f25e5e..3b211db5 100644
--- a/userapi/internal/api_logintoken.go
+++ b/userapi/internal/api_logintoken.go
@@ -66,7 +66,7 @@ func (a *UserInternalAPI) QueryLoginToken(ctx context.Context, req *api.QueryLog
 	if !a.Config.Matrix.IsLocalServerName(domain) {
 		return fmt.Errorf("cannot return a login token for a remote user (server name %s)", domain)
 	}
-	if _, err := a.DB.GetAccountByLocalpart(ctx, localpart); err != nil {
+	if _, err := a.DB.GetAccountByLocalpart(ctx, localpart, domain); err != nil {
 		res.Data = nil
 		if err == sql.ErrNoRows {
 			return nil
diff --git a/userapi/inthttp/client.go b/userapi/inthttp/client.go
index aa5d46d9..87ae058c 100644
--- a/userapi/inthttp/client.go
+++ b/userapi/inthttp/client.go
@@ -355,11 +355,12 @@ func (h *httpUserInternalAPI) SetAvatarURL(
 
 func (h *httpUserInternalAPI) QueryNumericLocalpart(
 	ctx context.Context,
+	request *api.QueryNumericLocalpartRequest,
 	response *api.QueryNumericLocalpartResponse,
 ) error {
 	return httputil.CallInternalRPCAPI(
 		"QueryNumericLocalpart", h.apiURL+QueryNumericLocalpartPath,
-		h.httpClient, ctx, &struct{}{}, response,
+		h.httpClient, ctx, request, response,
 	)
 }
 
diff --git a/userapi/inthttp/server.go b/userapi/inthttp/server.go
index 99148b76..661fecfa 100644
--- a/userapi/inthttp/server.go
+++ b/userapi/inthttp/server.go
@@ -15,12 +15,9 @@
 package inthttp
 
 import (
-	"net/http"
-
 	"github.com/gorilla/mux"
 	"github.com/matrix-org/dendrite/internal/httputil"
 	"github.com/matrix-org/dendrite/userapi/api"
-	"github.com/matrix-org/util"
 )
 
 // nolint: gocyclo
@@ -152,15 +149,9 @@ func AddRoutes(internalAPIMux *mux.Router, s api.UserInternalAPI) {
 		httputil.MakeInternalRPCAPI("UserAPIPerformSetAvatarURL", s.SetAvatarURL),
 	)
 
-	// TODO: Look at the shape of this
-	internalAPIMux.Handle(QueryNumericLocalpartPath,
-		httputil.MakeInternalAPI("UserAPIQueryNumericLocalpart", func(req *http.Request) util.JSONResponse {
-			response := api.QueryNumericLocalpartResponse{}
-			if err := s.QueryNumericLocalpart(req.Context(), &response); err != nil {
-				return util.ErrorResponse(err)
-			}
-			return util.JSONResponse{Code: http.StatusOK, JSON: &response}
-		}),
+	internalAPIMux.Handle(
+		QueryNumericLocalpartPath,
+		httputil.MakeInternalRPCAPI("UserAPIQueryNumericLocalpart", s.QueryNumericLocalpart),
 	)
 
 	internalAPIMux.Handle(
diff --git a/userapi/producers/syncapi.go b/userapi/producers/syncapi.go
index f556ea35..51eaa985 100644
--- a/userapi/producers/syncapi.go
+++ b/userapi/producers/syncapi.go
@@ -61,12 +61,12 @@ func (p *SyncAPI) SendAccountData(userID string, data eventutil.AccountData) err
 // GetAndSendNotificationData reads the database and sends data about unread
 // notifications to the Sync API server.
 func (p *SyncAPI) GetAndSendNotificationData(ctx context.Context, userID, roomID string) error {
-	localpart, _, err := gomatrixserverlib.SplitID('@', userID)
+	localpart, domain, err := gomatrixserverlib.SplitID('@', userID)
 	if err != nil {
 		return err
 	}
 
-	ntotal, nhighlight, err := p.db.GetRoomNotificationCounts(ctx, localpart, roomID)
+	ntotal, nhighlight, err := p.db.GetRoomNotificationCounts(ctx, localpart, domain, roomID)
 	if err != nil {
 		return err
 	}
diff --git a/userapi/storage/interface.go b/userapi/storage/interface.go
index 28ef2655..c22b7658 100644
--- a/userapi/storage/interface.go
+++ b/userapi/storage/interface.go
@@ -29,40 +29,40 @@ import (
 )
 
 type Profile interface {
-	GetProfileByLocalpart(ctx context.Context, localpart string) (*authtypes.Profile, error)
+	GetProfileByLocalpart(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName) (*authtypes.Profile, error)
 	SearchProfiles(ctx context.Context, searchString string, limit int) ([]authtypes.Profile, error)
-	SetAvatarURL(ctx context.Context, localpart string, avatarURL string) (*authtypes.Profile, bool, error)
-	SetDisplayName(ctx context.Context, localpart string, displayName string) (*authtypes.Profile, bool, error)
+	SetAvatarURL(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, avatarURL string) (*authtypes.Profile, bool, error)
+	SetDisplayName(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, displayName string) (*authtypes.Profile, bool, error)
 }
 
 type Account interface {
 	// CreateAccount makes a new account with the given login name and password, and creates an empty profile
 	// for this account. If no password is supplied, the account will be a passwordless account. If the
 	// account already exists, it will return nil, ErrUserExists.
-	CreateAccount(ctx context.Context, localpart string, plaintextPassword string, appserviceID string, accountType api.AccountType) (*api.Account, error)
-	GetAccountByPassword(ctx context.Context, localpart, plaintextPassword string) (*api.Account, error)
-	GetNewNumericLocalpart(ctx context.Context) (int64, error)
-	CheckAccountAvailability(ctx context.Context, localpart string) (bool, error)
-	GetAccountByLocalpart(ctx context.Context, localpart string) (*api.Account, error)
-	DeactivateAccount(ctx context.Context, localpart string) (err error)
-	SetPassword(ctx context.Context, localpart string, plaintextPassword string) error
+	CreateAccount(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, plaintextPassword string, appserviceID string, accountType api.AccountType) (*api.Account, error)
+	GetAccountByPassword(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, plaintextPassword string) (*api.Account, error)
+	GetNewNumericLocalpart(ctx context.Context, serverName gomatrixserverlib.ServerName) (int64, error)
+	CheckAccountAvailability(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName) (bool, error)
+	GetAccountByLocalpart(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName) (*api.Account, error)
+	DeactivateAccount(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName) (err error)
+	SetPassword(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, plaintextPassword string) error
 }
 
 type AccountData interface {
-	SaveAccountData(ctx context.Context, localpart, roomID, dataType string, content json.RawMessage) error
-	GetAccountData(ctx context.Context, localpart string) (global map[string]json.RawMessage, rooms map[string]map[string]json.RawMessage, err error)
+	SaveAccountData(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, roomID, dataType string, content json.RawMessage) error
+	GetAccountData(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName) (global map[string]json.RawMessage, rooms map[string]map[string]json.RawMessage, err error)
 	// GetAccountDataByType returns account data matching a given
 	// localpart, room ID and type.
 	// If no account data could be found, returns nil
 	// Returns an error if there was an issue with the retrieval
-	GetAccountDataByType(ctx context.Context, localpart, roomID, dataType string) (data json.RawMessage, err error)
-	QueryPushRules(ctx context.Context, localpart string) (*pushrules.AccountRuleSets, error)
+	GetAccountDataByType(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, roomID, dataType string) (data json.RawMessage, err error)
+	QueryPushRules(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName) (*pushrules.AccountRuleSets, error)
 }
 
 type Device interface {
 	GetDeviceByAccessToken(ctx context.Context, token string) (*api.Device, error)
-	GetDeviceByID(ctx context.Context, localpart, deviceID string) (*api.Device, error)
-	GetDevicesByLocalpart(ctx context.Context, localpart string) ([]api.Device, error)
+	GetDeviceByID(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, deviceID string) (*api.Device, error)
+	GetDevicesByLocalpart(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName) ([]api.Device, error)
 	GetDevicesByID(ctx context.Context, deviceIDs []string) ([]api.Device, error)
 	// CreateDevice makes a new device associated with the given user ID localpart.
 	// If there is already a device with the same device ID for this user, that access token will be revoked
@@ -70,12 +70,12 @@ type Device interface {
 	// an error will be returned.
 	// If no device ID is given one is generated.
 	// Returns the device on success.
-	CreateDevice(ctx context.Context, localpart string, deviceID *string, accessToken string, displayName *string, ipAddr, userAgent string) (dev *api.Device, returnErr error)
-	UpdateDevice(ctx context.Context, localpart, deviceID string, displayName *string) error
-	UpdateDeviceLastSeen(ctx context.Context, localpart, deviceID, ipAddr, userAgent string) error
-	RemoveDevices(ctx context.Context, localpart string, devices []string) error
+	CreateDevice(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, deviceID *string, accessToken string, displayName *string, ipAddr, userAgent string) (dev *api.Device, returnErr error)
+	UpdateDevice(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, deviceID string, displayName *string) error
+	UpdateDeviceLastSeen(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, deviceID, ipAddr, userAgent string) error
+	RemoveDevices(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, devices []string) error
 	// RemoveAllDevices deleted all devices for this user. Returns the devices deleted.
-	RemoveAllDevices(ctx context.Context, localpart, exceptDeviceID string) (devices []api.Device, err error)
+	RemoveAllDevices(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, exceptDeviceID string) (devices []api.Device, err error)
 }
 
 type KeyBackup interface {
@@ -107,26 +107,26 @@ type OpenID interface {
 }
 
 type Pusher interface {
-	UpsertPusher(ctx context.Context, p api.Pusher, localpart string) error
-	GetPushers(ctx context.Context, localpart string) ([]api.Pusher, error)
-	RemovePusher(ctx context.Context, appid, pushkey, localpart string) error
+	UpsertPusher(ctx context.Context, p api.Pusher, localpart string, serverName gomatrixserverlib.ServerName) error
+	GetPushers(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName) ([]api.Pusher, error)
+	RemovePusher(ctx context.Context, appid, pushkey, localpart string, serverName gomatrixserverlib.ServerName) error
 	RemovePushers(ctx context.Context, appid, pushkey string) error
 }
 
 type ThreePID interface {
-	SaveThreePIDAssociation(ctx context.Context, threepid, localpart, medium string) (err error)
+	SaveThreePIDAssociation(ctx context.Context, threepid, localpart string, serverName gomatrixserverlib.ServerName, medium string) (err error)
 	RemoveThreePIDAssociation(ctx context.Context, threepid string, medium string) (err error)
-	GetLocalpartForThreePID(ctx context.Context, threepid string, medium string) (localpart string, err error)
-	GetThreePIDsForLocalpart(ctx context.Context, localpart string) (threepids []authtypes.ThreePID, err error)
+	GetLocalpartForThreePID(ctx context.Context, threepid string, medium string) (localpart string, serverName gomatrixserverlib.ServerName, err error)
+	GetThreePIDsForLocalpart(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName) (threepids []authtypes.ThreePID, err error)
 }
 
 type Notification interface {
-	InsertNotification(ctx context.Context, localpart, eventID string, pos uint64, tweaks map[string]interface{}, n *api.Notification) error
-	DeleteNotificationsUpTo(ctx context.Context, localpart, roomID string, pos uint64) (affected bool, err error)
-	SetNotificationsRead(ctx context.Context, localpart, roomID string, pos uint64, read bool) (affected bool, err error)
-	GetNotifications(ctx context.Context, localpart string, fromID int64, limit int, filter tables.NotificationFilter) ([]*api.Notification, int64, error)
-	GetNotificationCount(ctx context.Context, localpart string, filter tables.NotificationFilter) (int64, error)
-	GetRoomNotificationCounts(ctx context.Context, localpart, roomID string) (total int64, highlight int64, _ error)
+	InsertNotification(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, eventID string, pos uint64, tweaks map[string]interface{}, n *api.Notification) error
+	DeleteNotificationsUpTo(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, roomID string, pos uint64) (affected bool, err error)
+	SetNotificationsRead(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, roomID string, pos uint64, read bool) (affected bool, err error)
+	GetNotifications(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, fromID int64, limit int, filter tables.NotificationFilter) ([]*api.Notification, int64, error)
+	GetNotificationCount(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, filter tables.NotificationFilter) (int64, error)
+	GetRoomNotificationCounts(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, roomID string) (total int64, highlight int64, _ error)
 	DeleteOldNotifications(ctx context.Context) error
 }
 
diff --git a/userapi/storage/postgres/account_data_table.go b/userapi/storage/postgres/account_data_table.go
index 0b6a3af6..2a4777d7 100644
--- a/userapi/storage/postgres/account_data_table.go
+++ b/userapi/storage/postgres/account_data_table.go
@@ -22,6 +22,7 @@ import (
 	"github.com/matrix-org/dendrite/internal"
 	"github.com/matrix-org/dendrite/internal/sqlutil"
 	"github.com/matrix-org/dendrite/userapi/storage/tables"
+	"github.com/matrix-org/gomatrixserverlib"
 )
 
 const accountDataSchema = `
@@ -29,27 +30,28 @@ const accountDataSchema = `
 CREATE TABLE IF NOT EXISTS userapi_account_datas (
     -- The Matrix user ID localpart for this account
     localpart TEXT NOT NULL,
+	server_name TEXT NOT NULL,
     -- The room ID for this data (empty string if not specific to a room)
     room_id TEXT,
     -- The account data type
     type TEXT NOT NULL,
     -- The account data content
-    content TEXT NOT NULL,
-
-    PRIMARY KEY(localpart, room_id, type)
+    content TEXT NOT NULL
 );
+
+CREATE UNIQUE INDEX IF NOT EXISTS userapi_account_datas_idx ON userapi_account_datas(localpart, server_name, room_id, type);
 `
 
 const insertAccountDataSQL = `
-	INSERT INTO userapi_account_datas(localpart, room_id, type, content) VALUES($1, $2, $3, $4)
-	ON CONFLICT (localpart, room_id, type) DO UPDATE SET content = EXCLUDED.content
+	INSERT INTO userapi_account_datas(localpart, server_name, room_id, type, content) VALUES($1, $2, $3, $4, $5)
+	ON CONFLICT (localpart, server_name, room_id, type) DO UPDATE SET content = EXCLUDED.content
 `
 
 const selectAccountDataSQL = "" +
-	"SELECT room_id, type, content FROM userapi_account_datas WHERE localpart = $1"
+	"SELECT room_id, type, content FROM userapi_account_datas WHERE localpart = $1 AND server_name = $2"
 
 const selectAccountDataByTypeSQL = "" +
-	"SELECT content FROM userapi_account_datas WHERE localpart = $1 AND room_id = $2 AND type = $3"
+	"SELECT content FROM userapi_account_datas WHERE localpart = $1 AND server_name = $2 AND room_id = $3 AND type = $4"
 
 type accountDataStatements struct {
 	insertAccountDataStmt       *sql.Stmt
@@ -71,21 +73,24 @@ func NewPostgresAccountDataTable(db *sql.DB) (tables.AccountDataTable, error) {
 }
 
 func (s *accountDataStatements) InsertAccountData(
-	ctx context.Context, txn *sql.Tx, localpart, roomID, dataType string, content json.RawMessage,
+	ctx context.Context, txn *sql.Tx,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	roomID, dataType string, content json.RawMessage,
 ) (err error) {
 	stmt := sqlutil.TxStmt(txn, s.insertAccountDataStmt)
-	_, err = stmt.ExecContext(ctx, localpart, roomID, dataType, content)
+	_, err = stmt.ExecContext(ctx, localpart, serverName, roomID, dataType, content)
 	return
 }
 
 func (s *accountDataStatements) SelectAccountData(
-	ctx context.Context, localpart string,
+	ctx context.Context,
+	localpart string, serverName gomatrixserverlib.ServerName,
 ) (
 	/* global */ map[string]json.RawMessage,
 	/* rooms */ map[string]map[string]json.RawMessage,
 	error,
 ) {
-	rows, err := s.selectAccountDataStmt.QueryContext(ctx, localpart)
+	rows, err := s.selectAccountDataStmt.QueryContext(ctx, localpart, serverName)
 	if err != nil {
 		return nil, nil, err
 	}
@@ -117,11 +122,13 @@ func (s *accountDataStatements) SelectAccountData(
 }
 
 func (s *accountDataStatements) SelectAccountDataByType(
-	ctx context.Context, localpart, roomID, dataType string,
+	ctx context.Context,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	roomID, dataType string,
 ) (data json.RawMessage, err error) {
 	var bytes []byte
 	stmt := s.selectAccountDataByTypeStmt
-	if err = stmt.QueryRowContext(ctx, localpart, roomID, dataType).Scan(&bytes); err != nil {
+	if err = stmt.QueryRowContext(ctx, localpart, serverName, roomID, dataType).Scan(&bytes); err != nil {
 		if err == sql.ErrNoRows {
 			return nil, nil
 		}
diff --git a/userapi/storage/postgres/accounts_table.go b/userapi/storage/postgres/accounts_table.go
index 7c309eb4..31a99652 100644
--- a/userapi/storage/postgres/accounts_table.go
+++ b/userapi/storage/postgres/accounts_table.go
@@ -17,6 +17,7 @@ package postgres
 import (
 	"context"
 	"database/sql"
+	"fmt"
 	"time"
 
 	"github.com/matrix-org/gomatrixserverlib"
@@ -34,7 +35,8 @@ const accountsSchema = `
 -- Stores data about accounts.
 CREATE TABLE IF NOT EXISTS userapi_accounts (
     -- The Matrix user ID localpart for this account
-    localpart TEXT NOT NULL PRIMARY KEY,
+    localpart TEXT NOT NULL,
+	server_name TEXT NOT NULL,
     -- When this account was first created, as a unix timestamp (ms resolution).
     created_ts BIGINT NOT NULL,
     -- The password hash for this account. Can be NULL if this is a passwordless account.
@@ -48,25 +50,27 @@ CREATE TABLE IF NOT EXISTS userapi_accounts (
     -- TODO:
     -- upgraded_ts, devices, any email reset stuff?
 );
+
+CREATE UNIQUE INDEX IF NOT EXISTS userapi_accounts_idx ON userapi_accounts(localpart, server_name);
 `
 
 const insertAccountSQL = "" +
-	"INSERT INTO userapi_accounts(localpart, created_ts, password_hash, appservice_id, account_type) VALUES ($1, $2, $3, $4, $5)"
+	"INSERT INTO userapi_accounts(localpart, server_name, created_ts, password_hash, appservice_id, account_type) VALUES ($1, $2, $3, $4, $5, $6)"
 
 const updatePasswordSQL = "" +
-	"UPDATE userapi_accounts SET password_hash = $1 WHERE localpart = $2"
+	"UPDATE userapi_accounts SET password_hash = $1 WHERE localpart = $2 AND server_name = $3"
 
 const deactivateAccountSQL = "" +
-	"UPDATE userapi_accounts SET is_deactivated = TRUE WHERE localpart = $1"
+	"UPDATE userapi_accounts SET is_deactivated = TRUE WHERE localpart = $1 AND server_name = $2"
 
 const selectAccountByLocalpartSQL = "" +
-	"SELECT localpart, appservice_id, account_type FROM userapi_accounts WHERE localpart = $1"
+	"SELECT localpart, server_name, appservice_id, account_type FROM userapi_accounts WHERE localpart = $1 AND server_name = $2"
 
 const selectPasswordHashSQL = "" +
-	"SELECT password_hash FROM userapi_accounts WHERE localpart = $1 AND is_deactivated = FALSE"
+	"SELECT password_hash FROM userapi_accounts WHERE localpart = $1 AND server_name = $2 AND is_deactivated = FALSE"
 
 const selectNewNumericLocalpartSQL = "" +
-	"SELECT COALESCE(MAX(localpart::bigint), 0) FROM userapi_accounts WHERE localpart ~ '^[0-9]{1,}$'"
+	"SELECT COALESCE(MAX(localpart::bigint), 0) FROM userapi_accounts WHERE localpart ~ '^[0-9]{1,}$' AND server_name = $1"
 
 type accountsStatements struct {
 	insertAccountStmt             *sql.Stmt
@@ -117,59 +121,62 @@ func NewPostgresAccountsTable(db *sql.DB, serverName gomatrixserverlib.ServerNam
 // this account will be passwordless. Returns an error if this account already exists. Returns the account
 // on success.
 func (s *accountsStatements) InsertAccount(
-	ctx context.Context, txn *sql.Tx, localpart, hash, appserviceID string, accountType api.AccountType,
+	ctx context.Context, txn *sql.Tx,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	hash, appserviceID string, accountType api.AccountType,
 ) (*api.Account, error) {
 	createdTimeMS := time.Now().UnixNano() / 1000000
 	stmt := sqlutil.TxStmt(txn, s.insertAccountStmt)
 
 	var err error
 	if accountType != api.AccountTypeAppService {
-		_, err = stmt.ExecContext(ctx, localpart, createdTimeMS, hash, nil, accountType)
+		_, err = stmt.ExecContext(ctx, localpart, serverName, createdTimeMS, hash, nil, accountType)
 	} else {
-		_, err = stmt.ExecContext(ctx, localpart, createdTimeMS, hash, appserviceID, accountType)
+		_, err = stmt.ExecContext(ctx, localpart, serverName, createdTimeMS, hash, appserviceID, accountType)
 	}
 	if err != nil {
-		return nil, err
+		return nil, fmt.Errorf("insertAccountStmt: %w", err)
 	}
 
 	return &api.Account{
 		Localpart:    localpart,
-		UserID:       userutil.MakeUserID(localpart, s.serverName),
-		ServerName:   s.serverName,
+		UserID:       userutil.MakeUserID(localpart, serverName),
+		ServerName:   serverName,
 		AppServiceID: appserviceID,
 		AccountType:  accountType,
 	}, nil
 }
 
 func (s *accountsStatements) UpdatePassword(
-	ctx context.Context, localpart, passwordHash string,
+	ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName,
+	passwordHash string,
 ) (err error) {
-	_, err = s.updatePasswordStmt.ExecContext(ctx, passwordHash, localpart)
+	_, err = s.updatePasswordStmt.ExecContext(ctx, passwordHash, localpart, serverName)
 	return
 }
 
 func (s *accountsStatements) DeactivateAccount(
-	ctx context.Context, localpart string,
+	ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName,
 ) (err error) {
-	_, err = s.deactivateAccountStmt.ExecContext(ctx, localpart)
+	_, err = s.deactivateAccountStmt.ExecContext(ctx, localpart, serverName)
 	return
 }
 
 func (s *accountsStatements) SelectPasswordHash(
-	ctx context.Context, localpart string,
+	ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName,
 ) (hash string, err error) {
-	err = s.selectPasswordHashStmt.QueryRowContext(ctx, localpart).Scan(&hash)
+	err = s.selectPasswordHashStmt.QueryRowContext(ctx, localpart, serverName).Scan(&hash)
 	return
 }
 
 func (s *accountsStatements) SelectAccountByLocalpart(
-	ctx context.Context, localpart string,
+	ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName,
 ) (*api.Account, error) {
 	var appserviceIDPtr sql.NullString
 	var acc api.Account
 
 	stmt := s.selectAccountByLocalpartStmt
-	err := stmt.QueryRowContext(ctx, localpart).Scan(&acc.Localpart, &appserviceIDPtr, &acc.AccountType)
+	err := stmt.QueryRowContext(ctx, localpart, serverName).Scan(&acc.Localpart, &acc.ServerName, &appserviceIDPtr, &acc.AccountType)
 	if err != nil {
 		if err != sql.ErrNoRows {
 			log.WithError(err).Error("Unable to retrieve user from the db")
@@ -180,19 +187,17 @@ func (s *accountsStatements) SelectAccountByLocalpart(
 		acc.AppServiceID = appserviceIDPtr.String
 	}
 
-	acc.UserID = userutil.MakeUserID(localpart, s.serverName)
-	acc.ServerName = s.serverName
-
+	acc.UserID = userutil.MakeUserID(acc.Localpart, acc.ServerName)
 	return &acc, nil
 }
 
 func (s *accountsStatements) SelectNewNumericLocalpart(
-	ctx context.Context, txn *sql.Tx,
+	ctx context.Context, txn *sql.Tx, serverName gomatrixserverlib.ServerName,
 ) (id int64, err error) {
 	stmt := s.selectNewNumericLocalpartStmt
 	if txn != nil {
 		stmt = sqlutil.TxStmt(txn, stmt)
 	}
-	err = stmt.QueryRowContext(ctx).Scan(&id)
+	err = stmt.QueryRowContext(ctx, serverName).Scan(&id)
 	return id + 1, err
 }
diff --git a/userapi/storage/postgres/deltas/2022110411000000_server_names.go b/userapi/storage/postgres/deltas/2022110411000000_server_names.go
new file mode 100644
index 00000000..279e1e5f
--- /dev/null
+++ b/userapi/storage/postgres/deltas/2022110411000000_server_names.go
@@ -0,0 +1,81 @@
+package deltas
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+
+	"github.com/lib/pq"
+	"github.com/matrix-org/gomatrixserverlib"
+)
+
+var serverNamesTables = []string{
+	"userapi_accounts",
+	"userapi_account_datas",
+	"userapi_devices",
+	"userapi_notifications",
+	"userapi_openid_tokens",
+	"userapi_profiles",
+	"userapi_pushers",
+	"userapi_threepids",
+}
+
+// These tables have a PRIMARY KEY constraint which we need to drop so
+// that we can recreate a new unique index that contains the server name.
+// If the new key doesn't exist (i.e. the database was created before the
+// table rename migration) we'll try to drop the old one instead.
+var serverNamesDropPK = map[string]string{
+	"userapi_accounts":      "account_accounts",
+	"userapi_account_datas": "account_data",
+	"userapi_profiles":      "account_profiles",
+}
+
+// These indices are out of date so let's drop them. They will get recreated
+// automatically.
+var serverNamesDropIndex = []string{
+	"userapi_pusher_localpart_idx",
+	"userapi_pusher_app_id_pushkey_localpart_idx",
+}
+
+// I know what you're thinking: you're wondering "why doesn't this use $1
+// and pass variadic parameters to ExecContext?" — the answer is because
+// PostgreSQL doesn't expect the table name to be specified as a substituted
+// argument in that way so it results in a syntax error in the query.
+
+func UpServerNames(ctx context.Context, tx *sql.Tx, serverName gomatrixserverlib.ServerName) error {
+	for _, table := range serverNamesTables {
+		q := fmt.Sprintf(
+			"ALTER TABLE IF EXISTS %s ADD COLUMN IF NOT EXISTS server_name TEXT NOT NULL DEFAULT '';",
+			pq.QuoteIdentifier(table),
+		)
+		if _, err := tx.ExecContext(ctx, q); err != nil {
+			return fmt.Errorf("add server name to %q error: %w", table, err)
+		}
+	}
+	for newTable, oldTable := range serverNamesDropPK {
+		q := fmt.Sprintf(
+			"ALTER TABLE IF EXISTS %s DROP CONSTRAINT IF EXISTS %s;",
+			pq.QuoteIdentifier(newTable), pq.QuoteIdentifier(newTable+"_pkey"),
+		)
+		if _, err := tx.ExecContext(ctx, q); err != nil {
+			return fmt.Errorf("drop new PK from %q error: %w", newTable, err)
+		}
+		q = fmt.Sprintf(
+			"ALTER TABLE IF EXISTS %s DROP CONSTRAINT IF EXISTS %s;",
+			pq.QuoteIdentifier(newTable), pq.QuoteIdentifier(oldTable+"_pkey"),
+		)
+		if _, err := tx.ExecContext(ctx, q); err != nil {
+			return fmt.Errorf("drop old PK from %q error: %w", newTable, err)
+		}
+	}
+	for _, index := range serverNamesDropIndex {
+		q := fmt.Sprintf(
+			"DROP INDEX IF EXISTS %s;",
+			pq.QuoteIdentifier(index),
+		)
+		if _, err := tx.ExecContext(ctx, q); err != nil {
+			return fmt.Errorf("drop index %q error: %w", index, err)
+		}
+	}
+	return nil
+}
diff --git a/userapi/storage/postgres/deltas/2022110411000001_server_names.go b/userapi/storage/postgres/deltas/2022110411000001_server_names.go
new file mode 100644
index 00000000..04a47fa7
--- /dev/null
+++ b/userapi/storage/postgres/deltas/2022110411000001_server_names.go
@@ -0,0 +1,28 @@
+package deltas
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+
+	"github.com/lib/pq"
+	"github.com/matrix-org/gomatrixserverlib"
+)
+
+// I know what you're thinking: you're wondering "why doesn't this use $1
+// and pass variadic parameters to ExecContext?" — the answer is because
+// PostgreSQL doesn't expect the table name to be specified as a substituted
+// argument in that way so it results in a syntax error in the query.
+
+func UpServerNamesPopulate(ctx context.Context, tx *sql.Tx, serverName gomatrixserverlib.ServerName) error {
+	for _, table := range serverNamesTables {
+		q := fmt.Sprintf(
+			"UPDATE %s SET server_name = %s WHERE server_name = '';",
+			pq.QuoteIdentifier(table), pq.QuoteLiteral(string(serverName)),
+		)
+		if _, err := tx.ExecContext(ctx, q); err != nil {
+			return fmt.Errorf("write server names to %q error: %w", table, err)
+		}
+	}
+	return nil
+}
diff --git a/userapi/storage/postgres/devices_table.go b/userapi/storage/postgres/devices_table.go
index 8b7fbd6c..2dd21618 100644
--- a/userapi/storage/postgres/devices_table.go
+++ b/userapi/storage/postgres/devices_table.go
@@ -17,6 +17,7 @@ package postgres
 import (
 	"context"
 	"database/sql"
+	"fmt"
 	"time"
 
 	"github.com/lib/pq"
@@ -50,6 +51,7 @@ CREATE TABLE IF NOT EXISTS userapi_devices (
     -- as it is smaller, makes it clearer that we only manage devices for our own users, and may make
     -- migration to different domain names easier.
     localpart TEXT NOT NULL,
+	server_name TEXT NOT NULL,
     -- When this devices was first recognised on the network, as a unix timestamp (ms resolution).
     created_ts BIGINT NOT NULL,
     -- The display name, human friendlier than device_id and updatable
@@ -65,39 +67,39 @@ CREATE TABLE IF NOT EXISTS userapi_devices (
 );
 
 -- Device IDs must be unique for a given user.
-CREATE UNIQUE INDEX IF NOT EXISTS userapi_device_localpart_id_idx ON userapi_devices(localpart, device_id);
+CREATE UNIQUE INDEX IF NOT EXISTS userapi_device_localpart_id_idx ON userapi_devices(localpart, server_name, device_id);
 `
 
 const insertDeviceSQL = "" +
-	"INSERT INTO userapi_devices(device_id, localpart, access_token, created_ts, display_name, last_seen_ts, ip, user_agent) VALUES ($1, $2, $3, $4, $5, $6, $7, $8)" +
+	"INSERT INTO userapi_devices(device_id, localpart, server_name, access_token, created_ts, display_name, last_seen_ts, ip, user_agent) VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9)" +
 	" RETURNING session_id"
 
 const selectDeviceByTokenSQL = "" +
-	"SELECT session_id, device_id, localpart FROM userapi_devices WHERE access_token = $1"
+	"SELECT session_id, device_id, localpart, server_name FROM userapi_devices WHERE access_token = $1"
 
 const selectDeviceByIDSQL = "" +
-	"SELECT display_name, last_seen_ts, ip FROM userapi_devices WHERE localpart = $1 and device_id = $2"
+	"SELECT display_name, last_seen_ts, ip FROM userapi_devices WHERE localpart = $1 AND server_name = $2 AND device_id = $3"
 
 const selectDevicesByLocalpartSQL = "" +
-	"SELECT device_id, display_name, last_seen_ts, ip, user_agent FROM userapi_devices WHERE localpart = $1 AND device_id != $2 ORDER BY last_seen_ts DESC"
+	"SELECT device_id, display_name, last_seen_ts, ip, user_agent FROM userapi_devices WHERE localpart = $1 AND server_name = $2 AND device_id != $3 ORDER BY last_seen_ts DESC"
 
 const updateDeviceNameSQL = "" +
-	"UPDATE userapi_devices SET display_name = $1 WHERE localpart = $2 AND device_id = $3"
+	"UPDATE userapi_devices SET display_name = $1 WHERE localpart = $2 AND server_name = $3 AND device_id = $4"
 
 const deleteDeviceSQL = "" +
-	"DELETE FROM userapi_devices WHERE device_id = $1 AND localpart = $2"
+	"DELETE FROM userapi_devices WHERE device_id = $1 AND localpart = $2 AND server_name = $3"
 
 const deleteDevicesByLocalpartSQL = "" +
-	"DELETE FROM userapi_devices WHERE localpart = $1 AND device_id != $2"
+	"DELETE FROM userapi_devices WHERE localpart = $1 AND server_name = $2 AND device_id != $3"
 
 const deleteDevicesSQL = "" +
-	"DELETE FROM userapi_devices WHERE localpart = $1 AND device_id = ANY($2)"
+	"DELETE FROM userapi_devices WHERE localpart = $1 AND server_name = $2 AND device_id = ANY($3)"
 
 const selectDevicesByIDSQL = "" +
-	"SELECT device_id, localpart, display_name, last_seen_ts FROM userapi_devices WHERE device_id = ANY($1) ORDER BY last_seen_ts DESC"
+	"SELECT device_id, localpart, server_name, display_name, last_seen_ts FROM userapi_devices WHERE device_id = ANY($1) ORDER BY last_seen_ts DESC"
 
 const updateDeviceLastSeen = "" +
-	"UPDATE userapi_devices SET last_seen_ts = $1, ip = $2, user_agent = $3 WHERE localpart = $4 AND device_id = $5"
+	"UPDATE userapi_devices SET last_seen_ts = $1, ip = $2, user_agent = $3 WHERE localpart = $4 AND server_name = $5 AND device_id = $6"
 
 type devicesStatements struct {
 	insertDeviceStmt             *sql.Stmt
@@ -148,18 +150,19 @@ func NewPostgresDevicesTable(db *sql.DB, serverName gomatrixserverlib.ServerName
 // Returns an error if the user already has a device with the given device ID.
 // Returns the device on success.
 func (s *devicesStatements) InsertDevice(
-	ctx context.Context, txn *sql.Tx, id, localpart, accessToken string,
-	displayName *string, ipAddr, userAgent string,
+	ctx context.Context, txn *sql.Tx, id string,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	accessToken string, displayName *string, ipAddr, userAgent string,
 ) (*api.Device, error) {
 	createdTimeMS := time.Now().UnixNano() / 1000000
 	var sessionID int64
 	stmt := sqlutil.TxStmt(txn, s.insertDeviceStmt)
-	if err := stmt.QueryRowContext(ctx, id, localpart, accessToken, createdTimeMS, displayName, createdTimeMS, ipAddr, userAgent).Scan(&sessionID); err != nil {
-		return nil, err
+	if err := stmt.QueryRowContext(ctx, id, localpart, serverName, accessToken, createdTimeMS, displayName, createdTimeMS, ipAddr, userAgent).Scan(&sessionID); err != nil {
+		return nil, fmt.Errorf("insertDeviceStmt: %w", err)
 	}
 	return &api.Device{
 		ID:          id,
-		UserID:      userutil.MakeUserID(localpart, s.serverName),
+		UserID:      userutil.MakeUserID(localpart, serverName),
 		AccessToken: accessToken,
 		SessionID:   sessionID,
 		LastSeenTS:  createdTimeMS,
@@ -170,38 +173,45 @@ func (s *devicesStatements) InsertDevice(
 
 // deleteDevice removes a single device by id and user localpart.
 func (s *devicesStatements) DeleteDevice(
-	ctx context.Context, txn *sql.Tx, id, localpart string,
+	ctx context.Context, txn *sql.Tx, id string,
+	localpart string, serverName gomatrixserverlib.ServerName,
 ) error {
 	stmt := sqlutil.TxStmt(txn, s.deleteDeviceStmt)
-	_, err := stmt.ExecContext(ctx, id, localpart)
+	_, err := stmt.ExecContext(ctx, id, localpart, serverName)
 	return err
 }
 
 // deleteDevices removes a single or multiple devices by ids and user localpart.
 // Returns an error if the execution failed.
 func (s *devicesStatements) DeleteDevices(
-	ctx context.Context, txn *sql.Tx, localpart string, devices []string,
+	ctx context.Context, txn *sql.Tx,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	devices []string,
 ) error {
 	stmt := sqlutil.TxStmt(txn, s.deleteDevicesStmt)
-	_, err := stmt.ExecContext(ctx, localpart, pq.Array(devices))
+	_, err := stmt.ExecContext(ctx, localpart, serverName, pq.Array(devices))
 	return err
 }
 
 // deleteDevicesByLocalpart removes all devices for the
 // given user localpart.
 func (s *devicesStatements) DeleteDevicesByLocalpart(
-	ctx context.Context, txn *sql.Tx, localpart, exceptDeviceID string,
+	ctx context.Context, txn *sql.Tx,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	exceptDeviceID string,
 ) error {
 	stmt := sqlutil.TxStmt(txn, s.deleteDevicesByLocalpartStmt)
-	_, err := stmt.ExecContext(ctx, localpart, exceptDeviceID)
+	_, err := stmt.ExecContext(ctx, localpart, serverName, exceptDeviceID)
 	return err
 }
 
 func (s *devicesStatements) UpdateDeviceName(
-	ctx context.Context, txn *sql.Tx, localpart, deviceID string, displayName *string,
+	ctx context.Context, txn *sql.Tx,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	deviceID string, displayName *string,
 ) error {
 	stmt := sqlutil.TxStmt(txn, s.updateDeviceNameStmt)
-	_, err := stmt.ExecContext(ctx, displayName, localpart, deviceID)
+	_, err := stmt.ExecContext(ctx, displayName, localpart, serverName, deviceID)
 	return err
 }
 
@@ -210,10 +220,11 @@ func (s *devicesStatements) SelectDeviceByToken(
 ) (*api.Device, error) {
 	var dev api.Device
 	var localpart string
+	var serverName gomatrixserverlib.ServerName
 	stmt := s.selectDeviceByTokenStmt
-	err := stmt.QueryRowContext(ctx, accessToken).Scan(&dev.SessionID, &dev.ID, &localpart)
+	err := stmt.QueryRowContext(ctx, accessToken).Scan(&dev.SessionID, &dev.ID, &localpart, &serverName)
 	if err == nil {
-		dev.UserID = userutil.MakeUserID(localpart, s.serverName)
+		dev.UserID = userutil.MakeUserID(localpart, serverName)
 		dev.AccessToken = accessToken
 	}
 	return &dev, err
@@ -222,16 +233,18 @@ func (s *devicesStatements) SelectDeviceByToken(
 // selectDeviceByID retrieves a device from the database with the given user
 // localpart and deviceID
 func (s *devicesStatements) SelectDeviceByID(
-	ctx context.Context, localpart, deviceID string,
+	ctx context.Context,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	deviceID string,
 ) (*api.Device, error) {
 	var dev api.Device
 	var displayName, ip sql.NullString
 	var lastseenTS sql.NullInt64
 	stmt := s.selectDeviceByIDStmt
-	err := stmt.QueryRowContext(ctx, localpart, deviceID).Scan(&displayName, &lastseenTS, &ip)
+	err := stmt.QueryRowContext(ctx, localpart, serverName, deviceID).Scan(&displayName, &lastseenTS, &ip)
 	if err == nil {
 		dev.ID = deviceID
-		dev.UserID = userutil.MakeUserID(localpart, s.serverName)
+		dev.UserID = userutil.MakeUserID(localpart, serverName)
 		if displayName.Valid {
 			dev.DisplayName = displayName.String
 		}
@@ -254,10 +267,11 @@ func (s *devicesStatements) SelectDevicesByID(ctx context.Context, deviceIDs []s
 	var devices []api.Device
 	var dev api.Device
 	var localpart string
+	var serverName gomatrixserverlib.ServerName
 	var lastseents sql.NullInt64
 	var displayName sql.NullString
 	for rows.Next() {
-		if err := rows.Scan(&dev.ID, &localpart, &displayName, &lastseents); err != nil {
+		if err := rows.Scan(&dev.ID, &localpart, &serverName, &displayName, &lastseents); err != nil {
 			return nil, err
 		}
 		if displayName.Valid {
@@ -266,17 +280,19 @@ func (s *devicesStatements) SelectDevicesByID(ctx context.Context, deviceIDs []s
 		if lastseents.Valid {
 			dev.LastSeenTS = lastseents.Int64
 		}
-		dev.UserID = userutil.MakeUserID(localpart, s.serverName)
+		dev.UserID = userutil.MakeUserID(localpart, serverName)
 		devices = append(devices, dev)
 	}
 	return devices, rows.Err()
 }
 
 func (s *devicesStatements) SelectDevicesByLocalpart(
-	ctx context.Context, txn *sql.Tx, localpart, exceptDeviceID string,
+	ctx context.Context, txn *sql.Tx,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	exceptDeviceID string,
 ) ([]api.Device, error) {
 	devices := []api.Device{}
-	rows, err := sqlutil.TxStmt(txn, s.selectDevicesByLocalpartStmt).QueryContext(ctx, localpart, exceptDeviceID)
+	rows, err := sqlutil.TxStmt(txn, s.selectDevicesByLocalpartStmt).QueryContext(ctx, localpart, serverName, exceptDeviceID)
 
 	if err != nil {
 		return devices, err
@@ -307,16 +323,16 @@ func (s *devicesStatements) SelectDevicesByLocalpart(
 			dev.UserAgent = useragent.String
 		}
 
-		dev.UserID = userutil.MakeUserID(localpart, s.serverName)
+		dev.UserID = userutil.MakeUserID(localpart, serverName)
 		devices = append(devices, dev)
 	}
 
 	return devices, rows.Err()
 }
 
-func (s *devicesStatements) UpdateDeviceLastSeen(ctx context.Context, txn *sql.Tx, localpart, deviceID, ipAddr, userAgent string) error {
+func (s *devicesStatements) UpdateDeviceLastSeen(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, deviceID, ipAddr, userAgent string) error {
 	lastSeenTs := time.Now().UnixNano() / 1000000
 	stmt := sqlutil.TxStmt(txn, s.updateDeviceLastSeenStmt)
-	_, err := stmt.ExecContext(ctx, lastSeenTs, ipAddr, userAgent, localpart, deviceID)
+	_, err := stmt.ExecContext(ctx, lastSeenTs, ipAddr, userAgent, localpart, serverName, deviceID)
 	return err
 }
diff --git a/userapi/storage/postgres/notifications_table.go b/userapi/storage/postgres/notifications_table.go
index 24a30b2f..dc64b1e7 100644
--- a/userapi/storage/postgres/notifications_table.go
+++ b/userapi/storage/postgres/notifications_table.go
@@ -43,6 +43,7 @@ const notificationSchema = `
 CREATE TABLE IF NOT EXISTS userapi_notifications (
     id BIGSERIAL PRIMARY KEY,
 	localpart TEXT NOT NULL,
+	server_name TEXT NOT NULL,
 	room_id TEXT NOT NULL,
 	event_id TEXT NOT NULL,
 	stream_pos BIGINT NOT NULL,
@@ -52,33 +53,33 @@ CREATE TABLE IF NOT EXISTS userapi_notifications (
     read BOOLEAN NOT NULL DEFAULT FALSE
 );
 
-CREATE INDEX IF NOT EXISTS userapi_notification_localpart_room_id_event_id_idx ON userapi_notifications(localpart, room_id, event_id);
-CREATE INDEX IF NOT EXISTS userapi_notification_localpart_room_id_id_idx ON userapi_notifications(localpart, room_id, id);
-CREATE INDEX IF NOT EXISTS userapi_notification_localpart_id_idx ON userapi_notifications(localpart, id);
+CREATE INDEX IF NOT EXISTS userapi_notification_localpart_room_id_event_id_idx ON userapi_notifications(localpart, server_name, room_id, event_id);
+CREATE INDEX IF NOT EXISTS userapi_notification_localpart_room_id_id_idx ON userapi_notifications(localpart, server_name, room_id, id);
+CREATE INDEX IF NOT EXISTS userapi_notification_localpart_id_idx ON userapi_notifications(localpart, server_name, id);
 `
 
 const insertNotificationSQL = "" +
-	"INSERT INTO userapi_notifications (localpart, room_id, event_id, stream_pos, ts_ms, highlight, notification_json) VALUES ($1, $2, $3, $4, $5, $6, $7)"
+	"INSERT INTO userapi_notifications (localpart, server_name, room_id, event_id, stream_pos, ts_ms, highlight, notification_json) VALUES ($1, $2, $3, $4, $5, $6, $7, $8)"
 
 const deleteNotificationsUpToSQL = "" +
-	"DELETE FROM userapi_notifications WHERE localpart = $1 AND room_id = $2 AND stream_pos <= $3"
+	"DELETE FROM userapi_notifications WHERE localpart = $1 AND server_name = $2 AND room_id = $3 AND stream_pos <= $4"
 
 const updateNotificationReadSQL = "" +
-	"UPDATE userapi_notifications SET read = $1 WHERE localpart = $2 AND room_id = $3 AND stream_pos <= $4 AND read <> $1"
+	"UPDATE userapi_notifications SET read = $1 WHERE localpart = $2 AND server_name = $3 AND room_id = $4 AND stream_pos <= $5 AND read <> $1"
 
 const selectNotificationSQL = "" +
-	"SELECT id, room_id, ts_ms, read, notification_json FROM userapi_notifications WHERE localpart = $1 AND id > $2 AND (" +
-	"(($3 & 1) <> 0 AND highlight) OR (($3 & 2) <> 0 AND NOT highlight)" +
-	") AND NOT read ORDER BY localpart, id LIMIT $4"
+	"SELECT id, room_id, ts_ms, read, notification_json FROM userapi_notifications WHERE localpart = $1 AND server_name = $2 AND id > $3 AND (" +
+	"(($4 & 1) <> 0 AND highlight) OR (($4 & 2) <> 0 AND NOT highlight)" +
+	") AND NOT read ORDER BY localpart, id LIMIT $5"
 
 const selectNotificationCountSQL = "" +
-	"SELECT COUNT(*) FROM userapi_notifications WHERE localpart = $1 AND (" +
-	"(($2 & 1) <> 0 AND highlight) OR (($2 & 2) <> 0 AND NOT highlight)" +
+	"SELECT COUNT(*) FROM userapi_notifications WHERE localpart = $1 AND server_name = $2 AND (" +
+	"(($3 & 1) <> 0 AND highlight) OR (($3 & 2) <> 0 AND NOT highlight)" +
 	") AND NOT read"
 
 const selectRoomNotificationCountsSQL = "" +
 	"SELECT COUNT(*), COUNT(*) FILTER (WHERE highlight) FROM userapi_notifications " +
-	"WHERE localpart = $1 AND room_id = $2 AND NOT read"
+	"WHERE localpart = $1 AND server_name = $2 AND room_id = $3 AND NOT read"
 
 const cleanNotificationsSQL = "" +
 	"DELETE FROM userapi_notifications WHERE" +
@@ -111,7 +112,7 @@ func (s *notificationsStatements) Clean(ctx context.Context, txn *sql.Tx) error
 }
 
 // Insert inserts a notification into the database.
-func (s *notificationsStatements) Insert(ctx context.Context, txn *sql.Tx, localpart, eventID string, pos uint64, highlight bool, n *api.Notification) error {
+func (s *notificationsStatements) Insert(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, eventID string, pos uint64, highlight bool, n *api.Notification) error {
 	roomID, tsMS := n.RoomID, n.TS
 	nn := *n
 	// Clears out fields that have their own columns to (1) shrink the
@@ -122,13 +123,13 @@ func (s *notificationsStatements) Insert(ctx context.Context, txn *sql.Tx, local
 	if err != nil {
 		return err
 	}
-	_, err = sqlutil.TxStmt(txn, s.insertStmt).ExecContext(ctx, localpart, roomID, eventID, pos, tsMS, highlight, string(bs))
+	_, err = sqlutil.TxStmt(txn, s.insertStmt).ExecContext(ctx, localpart, serverName, roomID, eventID, pos, tsMS, highlight, string(bs))
 	return err
 }
 
 // DeleteUpTo deletes all previous notifications, up to and including the event.
-func (s *notificationsStatements) DeleteUpTo(ctx context.Context, txn *sql.Tx, localpart, roomID string, pos uint64) (affected bool, _ error) {
-	res, err := sqlutil.TxStmt(txn, s.deleteUpToStmt).ExecContext(ctx, localpart, roomID, pos)
+func (s *notificationsStatements) DeleteUpTo(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, roomID string, pos uint64) (affected bool, _ error) {
+	res, err := sqlutil.TxStmt(txn, s.deleteUpToStmt).ExecContext(ctx, localpart, serverName, roomID, pos)
 	if err != nil {
 		return false, err
 	}
@@ -141,8 +142,8 @@ func (s *notificationsStatements) DeleteUpTo(ctx context.Context, txn *sql.Tx, l
 }
 
 // UpdateRead updates the "read" value for an event.
-func (s *notificationsStatements) UpdateRead(ctx context.Context, txn *sql.Tx, localpart, roomID string, pos uint64, v bool) (affected bool, _ error) {
-	res, err := sqlutil.TxStmt(txn, s.updateReadStmt).ExecContext(ctx, v, localpart, roomID, pos)
+func (s *notificationsStatements) UpdateRead(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, roomID string, pos uint64, v bool) (affected bool, _ error) {
+	res, err := sqlutil.TxStmt(txn, s.updateReadStmt).ExecContext(ctx, v, localpart, serverName, roomID, pos)
 	if err != nil {
 		return false, err
 	}
@@ -154,8 +155,8 @@ func (s *notificationsStatements) UpdateRead(ctx context.Context, txn *sql.Tx, l
 	return nrows > 0, nil
 }
 
-func (s *notificationsStatements) Select(ctx context.Context, txn *sql.Tx, localpart string, fromID int64, limit int, filter tables.NotificationFilter) ([]*api.Notification, int64, error) {
-	rows, err := sqlutil.TxStmt(txn, s.selectStmt).QueryContext(ctx, localpart, fromID, uint32(filter), limit)
+func (s *notificationsStatements) Select(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, fromID int64, limit int, filter tables.NotificationFilter) ([]*api.Notification, int64, error) {
+	rows, err := sqlutil.TxStmt(txn, s.selectStmt).QueryContext(ctx, localpart, serverName, fromID, uint32(filter), limit)
 
 	if err != nil {
 		return nil, 0, err
@@ -197,12 +198,12 @@ func (s *notificationsStatements) Select(ctx context.Context, txn *sql.Tx, local
 	return notifs, maxID, rows.Err()
 }
 
-func (s *notificationsStatements) SelectCount(ctx context.Context, txn *sql.Tx, localpart string, filter tables.NotificationFilter) (count int64, err error) {
-	err = sqlutil.TxStmt(txn, s.selectCountStmt).QueryRowContext(ctx, localpart, uint32(filter)).Scan(&count)
+func (s *notificationsStatements) SelectCount(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, filter tables.NotificationFilter) (count int64, err error) {
+	err = sqlutil.TxStmt(txn, s.selectCountStmt).QueryRowContext(ctx, localpart, serverName, uint32(filter)).Scan(&count)
 	return
 }
 
-func (s *notificationsStatements) SelectRoomCounts(ctx context.Context, txn *sql.Tx, localpart, roomID string) (total int64, highlight int64, err error) {
-	err = sqlutil.TxStmt(txn, s.selectRoomCountsStmt).QueryRowContext(ctx, localpart, roomID).Scan(&total, &highlight)
+func (s *notificationsStatements) SelectRoomCounts(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, roomID string) (total int64, highlight int64, err error) {
+	err = sqlutil.TxStmt(txn, s.selectRoomCountsStmt).QueryRowContext(ctx, localpart, serverName, roomID).Scan(&total, &highlight)
 	return
 }
diff --git a/userapi/storage/postgres/openid_table.go b/userapi/storage/postgres/openid_table.go
index 06ae30d0..68d87f00 100644
--- a/userapi/storage/postgres/openid_table.go
+++ b/userapi/storage/postgres/openid_table.go
@@ -3,6 +3,7 @@ package postgres
 import (
 	"context"
 	"database/sql"
+	"fmt"
 
 	"github.com/matrix-org/dendrite/internal/sqlutil"
 	"github.com/matrix-org/dendrite/userapi/api"
@@ -18,16 +19,17 @@ CREATE TABLE IF NOT EXISTS userapi_openid_tokens (
 	token TEXT NOT NULL PRIMARY KEY,
     -- The Matrix user ID for this account
 	localpart TEXT NOT NULL,
+	server_name TEXT NOT NULL,
 	-- When the token expires, as a unix timestamp (ms resolution).
 	token_expires_at_ms BIGINT NOT NULL
 );
 `
 
 const insertOpenIDTokenSQL = "" +
-	"INSERT INTO userapi_openid_tokens(token, localpart, token_expires_at_ms) VALUES ($1, $2, $3)"
+	"INSERT INTO userapi_openid_tokens(token, localpart, server_name, token_expires_at_ms) VALUES ($1, $2, $3, $4)"
 
 const selectOpenIDTokenSQL = "" +
-	"SELECT localpart, token_expires_at_ms FROM userapi_openid_tokens WHERE token = $1"
+	"SELECT localpart, server_name, token_expires_at_ms FROM userapi_openid_tokens WHERE token = $1"
 
 type openIDTokenStatements struct {
 	insertTokenStmt *sql.Stmt
@@ -54,11 +56,11 @@ func NewPostgresOpenIDTable(db *sql.DB, serverName gomatrixserverlib.ServerName)
 func (s *openIDTokenStatements) InsertOpenIDToken(
 	ctx context.Context,
 	txn *sql.Tx,
-	token, localpart string,
+	token, localpart string, serverName gomatrixserverlib.ServerName,
 	expiresAtMS int64,
 ) (err error) {
 	stmt := sqlutil.TxStmt(txn, s.insertTokenStmt)
-	_, err = stmt.ExecContext(ctx, token, localpart, expiresAtMS)
+	_, err = stmt.ExecContext(ctx, token, localpart, serverName, expiresAtMS)
 	return
 }
 
@@ -69,10 +71,13 @@ func (s *openIDTokenStatements) SelectOpenIDTokenAtrributes(
 	token string,
 ) (*api.OpenIDTokenAttributes, error) {
 	var openIDTokenAttrs api.OpenIDTokenAttributes
+	var localpart string
+	var serverName gomatrixserverlib.ServerName
 	err := s.selectTokenStmt.QueryRowContext(ctx, token).Scan(
-		&openIDTokenAttrs.UserID,
+		&localpart, &serverName,
 		&openIDTokenAttrs.ExpiresAtMS,
 	)
+	openIDTokenAttrs.UserID = fmt.Sprintf("@%s:%s", localpart, serverName)
 	if err != nil {
 		if err != sql.ErrNoRows {
 			log.WithError(err).Error("Unable to retrieve token from the db")
diff --git a/userapi/storage/postgres/profile_table.go b/userapi/storage/postgres/profile_table.go
index 2753b23d..df4e0db6 100644
--- a/userapi/storage/postgres/profile_table.go
+++ b/userapi/storage/postgres/profile_table.go
@@ -23,42 +23,46 @@ import (
 	"github.com/matrix-org/dendrite/internal"
 	"github.com/matrix-org/dendrite/internal/sqlutil"
 	"github.com/matrix-org/dendrite/userapi/storage/tables"
+	"github.com/matrix-org/gomatrixserverlib"
 )
 
 const profilesSchema = `
 -- Stores data about accounts profiles.
 CREATE TABLE IF NOT EXISTS userapi_profiles (
     -- The Matrix user ID localpart for this account
-    localpart TEXT NOT NULL PRIMARY KEY,
+    localpart TEXT NOT NULL,
+	server_name TEXT NOT NULL,
     -- The display name for this account
     display_name TEXT,
     -- The URL of the avatar for this account
     avatar_url TEXT
 );
+
+CREATE UNIQUE INDEX IF NOT EXISTS userapi_profiles_idx ON userapi_profiles(localpart, server_name);
 `
 
 const insertProfileSQL = "" +
-	"INSERT INTO userapi_profiles(localpart, display_name, avatar_url) VALUES ($1, $2, $3)"
+	"INSERT INTO userapi_profiles(localpart, server_name, display_name, avatar_url) VALUES ($1, $2, $3, $4)"
 
 const selectProfileByLocalpartSQL = "" +
-	"SELECT localpart, display_name, avatar_url FROM userapi_profiles WHERE localpart = $1"
+	"SELECT localpart, server_name, display_name, avatar_url FROM userapi_profiles WHERE localpart = $1 AND server_name = $2"
 
 const setAvatarURLSQL = "" +
 	"UPDATE userapi_profiles AS new" +
 	" SET avatar_url = $1" +
 	" FROM userapi_profiles AS old" +
-	" WHERE new.localpart = $2" +
+	" WHERE new.localpart = $2 AND new.server_name = $3" +
 	" RETURNING new.display_name, old.avatar_url <> new.avatar_url"
 
 const setDisplayNameSQL = "" +
 	"UPDATE userapi_profiles AS new" +
 	" SET display_name = $1" +
 	" FROM userapi_profiles AS old" +
-	" WHERE new.localpart = $2" +
+	" WHERE new.localpart = $2 AND new.server_name = $3" +
 	" RETURNING new.avatar_url, old.display_name <> new.display_name"
 
 const selectProfilesBySearchSQL = "" +
-	"SELECT localpart, display_name, avatar_url FROM userapi_profiles WHERE localpart LIKE $1 OR display_name LIKE $1 LIMIT $2"
+	"SELECT localpart, server_name, display_name, avatar_url FROM userapi_profiles WHERE localpart LIKE $1 OR display_name LIKE $1 LIMIT $2"
 
 type profilesStatements struct {
 	serverNoticesLocalpart       string
@@ -87,18 +91,20 @@ func NewPostgresProfilesTable(db *sql.DB, serverNoticesLocalpart string) (tables
 }
 
 func (s *profilesStatements) InsertProfile(
-	ctx context.Context, txn *sql.Tx, localpart string,
+	ctx context.Context, txn *sql.Tx,
+	localpart string, serverName gomatrixserverlib.ServerName,
 ) (err error) {
-	_, err = sqlutil.TxStmt(txn, s.insertProfileStmt).ExecContext(ctx, localpart, "", "")
+	_, err = sqlutil.TxStmt(txn, s.insertProfileStmt).ExecContext(ctx, localpart, serverName, "", "")
 	return
 }
 
 func (s *profilesStatements) SelectProfileByLocalpart(
-	ctx context.Context, localpart string,
+	ctx context.Context,
+	localpart string, serverName gomatrixserverlib.ServerName,
 ) (*authtypes.Profile, error) {
 	var profile authtypes.Profile
-	err := s.selectProfileByLocalpartStmt.QueryRowContext(ctx, localpart).Scan(
-		&profile.Localpart, &profile.DisplayName, &profile.AvatarURL,
+	err := s.selectProfileByLocalpartStmt.QueryRowContext(ctx, localpart, serverName).Scan(
+		&profile.Localpart, &profile.ServerName, &profile.DisplayName, &profile.AvatarURL,
 	)
 	if err != nil {
 		return nil, err
@@ -107,28 +113,34 @@ func (s *profilesStatements) SelectProfileByLocalpart(
 }
 
 func (s *profilesStatements) SetAvatarURL(
-	ctx context.Context, txn *sql.Tx, localpart string, avatarURL string,
+	ctx context.Context, txn *sql.Tx,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	avatarURL string,
 ) (*authtypes.Profile, bool, error) {
 	profile := &authtypes.Profile{
-		Localpart: localpart,
-		AvatarURL: avatarURL,
+		Localpart:  localpart,
+		ServerName: string(serverName),
+		AvatarURL:  avatarURL,
 	}
 	var changed bool
 	stmt := sqlutil.TxStmt(txn, s.setAvatarURLStmt)
-	err := stmt.QueryRowContext(ctx, avatarURL, localpart).Scan(&profile.DisplayName, &changed)
+	err := stmt.QueryRowContext(ctx, avatarURL, localpart, serverName).Scan(&profile.DisplayName, &changed)
 	return profile, changed, err
 }
 
 func (s *profilesStatements) SetDisplayName(
-	ctx context.Context, txn *sql.Tx, localpart string, displayName string,
+	ctx context.Context, txn *sql.Tx,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	displayName string,
 ) (*authtypes.Profile, bool, error) {
 	profile := &authtypes.Profile{
 		Localpart:   localpart,
+		ServerName:  string(serverName),
 		DisplayName: displayName,
 	}
 	var changed bool
 	stmt := sqlutil.TxStmt(txn, s.setDisplayNameStmt)
-	err := stmt.QueryRowContext(ctx, displayName, localpart).Scan(&profile.AvatarURL, &changed)
+	err := stmt.QueryRowContext(ctx, displayName, localpart, serverName).Scan(&profile.AvatarURL, &changed)
 	return profile, changed, err
 }
 
@@ -146,7 +158,7 @@ func (s *profilesStatements) SelectProfilesBySearch(
 	defer internal.CloseAndLogIfError(ctx, rows, "selectProfilesBySearch: rows.close() failed")
 	for rows.Next() {
 		var profile authtypes.Profile
-		if err := rows.Scan(&profile.Localpart, &profile.DisplayName, &profile.AvatarURL); err != nil {
+		if err := rows.Scan(&profile.Localpart, &profile.ServerName, &profile.DisplayName, &profile.AvatarURL); err != nil {
 			return nil, err
 		}
 		if profile.Localpart != s.serverNoticesLocalpart {
diff --git a/userapi/storage/postgres/pusher_table.go b/userapi/storage/postgres/pusher_table.go
index 6fb714fb..707b3bd2 100644
--- a/userapi/storage/postgres/pusher_table.go
+++ b/userapi/storage/postgres/pusher_table.go
@@ -25,6 +25,7 @@ import (
 	"github.com/matrix-org/dendrite/internal/sqlutil"
 	"github.com/matrix-org/dendrite/userapi/api"
 	"github.com/matrix-org/dendrite/userapi/storage/tables"
+	"github.com/matrix-org/gomatrixserverlib"
 )
 
 // See https://matrix.org/docs/spec/client_server/r0.6.1#get-matrix-client-r0-pushers
@@ -33,6 +34,7 @@ CREATE TABLE IF NOT EXISTS userapi_pushers (
 	id BIGSERIAL PRIMARY KEY,
 	-- The Matrix user ID localpart for this pusher
 	localpart TEXT NOT NULL,
+	server_name TEXT NOT NULL,
 	session_id BIGINT DEFAULT NULL,
 	profile_tag TEXT,
 	kind TEXT NOT NULL,
@@ -49,22 +51,22 @@ CREATE TABLE IF NOT EXISTS userapi_pushers (
 CREATE INDEX IF NOT EXISTS userapi_pusher_app_id_pushkey_idx ON userapi_pushers(app_id, pushkey);
 
 -- For faster retrieving by localpart.
-CREATE INDEX IF NOT EXISTS userapi_pusher_localpart_idx ON userapi_pushers(localpart);
+CREATE INDEX IF NOT EXISTS userapi_pusher_localpart_idx ON userapi_pushers(localpart, server_name);
 
 -- Pushkey must be unique for a given user and app.
-CREATE UNIQUE INDEX IF NOT EXISTS userapi_pusher_app_id_pushkey_localpart_idx ON userapi_pushers(app_id, pushkey, localpart);
+CREATE UNIQUE INDEX IF NOT EXISTS userapi_pusher_app_id_pushkey_localpart_idx ON userapi_pushers(app_id, pushkey, localpart, server_name);
 `
 
 const insertPusherSQL = "" +
-	"INSERT INTO userapi_pushers (localpart, session_id, pushkey, pushkey_ts_ms, kind, app_id, app_display_name, device_display_name, profile_tag, lang, data)" +
-	"VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11)" +
-	"ON CONFLICT (app_id, pushkey, localpart) DO UPDATE SET session_id = $2, pushkey_ts_ms = $4, kind = $5, app_display_name = $7, device_display_name = $8, profile_tag = $9, lang = $10, data = $11"
+	"INSERT INTO userapi_pushers (localpart, server_name, session_id, pushkey, pushkey_ts_ms, kind, app_id, app_display_name, device_display_name, profile_tag, lang, data)" +
+	"VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11, $12)" +
+	"ON CONFLICT (app_id, pushkey, localpart, server_name) DO UPDATE SET session_id = $3, pushkey_ts_ms = $5, kind = $6, app_display_name = $8, device_display_name = $9, profile_tag = $10, lang = $11, data = $12"
 
 const selectPushersSQL = "" +
-	"SELECT session_id, pushkey, pushkey_ts_ms, kind, app_id, app_display_name, device_display_name, profile_tag, lang, data FROM userapi_pushers WHERE localpart = $1"
+	"SELECT session_id, pushkey, pushkey_ts_ms, kind, app_id, app_display_name, device_display_name, profile_tag, lang, data FROM userapi_pushers WHERE localpart = $1 AND server_name = $2"
 
 const deletePusherSQL = "" +
-	"DELETE FROM userapi_pushers WHERE app_id = $1 AND pushkey = $2 AND localpart = $3"
+	"DELETE FROM userapi_pushers WHERE app_id = $1 AND pushkey = $2 AND localpart = $3 AND server_name = $4"
 
 const deletePushersByAppIdAndPushKeySQL = "" +
 	"DELETE FROM userapi_pushers WHERE app_id = $1 AND pushkey = $2"
@@ -95,18 +97,19 @@ type pushersStatements struct {
 // Returns nil error success.
 func (s *pushersStatements) InsertPusher(
 	ctx context.Context, txn *sql.Tx, session_id int64,
-	pushkey string, pushkeyTS int64, kind api.PusherKind, appid, appdisplayname, devicedisplayname, profiletag, lang, data, localpart string,
+	pushkey string, pushkeyTS int64, kind api.PusherKind, appid, appdisplayname, devicedisplayname, profiletag, lang, data,
+	localpart string, serverName gomatrixserverlib.ServerName,
 ) error {
-	_, err := sqlutil.TxStmt(txn, s.insertPusherStmt).ExecContext(ctx, localpart, session_id, pushkey, pushkeyTS, kind, appid, appdisplayname, devicedisplayname, profiletag, lang, data)
-	logrus.Debugf("Created pusher %d", session_id)
+	_, err := sqlutil.TxStmt(txn, s.insertPusherStmt).ExecContext(ctx, localpart, serverName, session_id, pushkey, pushkeyTS, kind, appid, appdisplayname, devicedisplayname, profiletag, lang, data)
 	return err
 }
 
 func (s *pushersStatements) SelectPushers(
-	ctx context.Context, txn *sql.Tx, localpart string,
+	ctx context.Context, txn *sql.Tx,
+	localpart string, serverName gomatrixserverlib.ServerName,
 ) ([]api.Pusher, error) {
 	pushers := []api.Pusher{}
-	rows, err := sqlutil.TxStmt(txn, s.selectPushersStmt).QueryContext(ctx, localpart)
+	rows, err := sqlutil.TxStmt(txn, s.selectPushersStmt).QueryContext(ctx, localpart, serverName)
 
 	if err != nil {
 		return pushers, err
@@ -143,9 +146,10 @@ func (s *pushersStatements) SelectPushers(
 
 // deletePusher removes a single pusher by pushkey and user localpart.
 func (s *pushersStatements) DeletePusher(
-	ctx context.Context, txn *sql.Tx, appid, pushkey, localpart string,
+	ctx context.Context, txn *sql.Tx, appid, pushkey,
+	localpart string, serverName gomatrixserverlib.ServerName,
 ) error {
-	_, err := sqlutil.TxStmt(txn, s.deletePusherStmt).ExecContext(ctx, appid, pushkey, localpart)
+	_, err := sqlutil.TxStmt(txn, s.deletePusherStmt).ExecContext(ctx, appid, pushkey, localpart, serverName)
 	return err
 }
 
diff --git a/userapi/storage/postgres/storage.go b/userapi/storage/postgres/storage.go
index c059e3e6..92dc4808 100644
--- a/userapi/storage/postgres/storage.go
+++ b/userapi/storage/postgres/storage.go
@@ -15,6 +15,8 @@
 package postgres
 
 import (
+	"context"
+	"database/sql"
 	"fmt"
 	"time"
 
@@ -43,18 +45,24 @@ func NewDatabase(base *base.BaseDendrite, dbProperties *config.DatabaseOptions,
 		Up:      deltas.UpRenameTables,
 		Down:    deltas.DownRenameTables,
 	})
+	m.AddMigrations(sqlutil.Migration{
+		Version: "userapi: server names",
+		Up: func(ctx context.Context, txn *sql.Tx) error {
+			return deltas.UpServerNames(ctx, txn, serverName)
+		},
+	})
 	if err = m.Up(base.Context()); err != nil {
 		return nil, err
 	}
 
-	accountDataTable, err := NewPostgresAccountDataTable(db)
-	if err != nil {
-		return nil, fmt.Errorf("NewPostgresAccountDataTable: %w", err)
-	}
 	accountsTable, err := NewPostgresAccountsTable(db, serverName)
 	if err != nil {
 		return nil, fmt.Errorf("NewPostgresAccountsTable: %w", err)
 	}
+	accountDataTable, err := NewPostgresAccountDataTable(db)
+	if err != nil {
+		return nil, fmt.Errorf("NewPostgresAccountDataTable: %w", err)
+	}
 	devicesTable, err := NewPostgresDevicesTable(db, serverName)
 	if err != nil {
 		return nil, fmt.Errorf("NewPostgresDevicesTable: %w", err)
@@ -95,6 +103,18 @@ func NewDatabase(base *base.BaseDendrite, dbProperties *config.DatabaseOptions,
 	if err != nil {
 		return nil, fmt.Errorf("NewPostgresStatsTable: %w", err)
 	}
+
+	m = sqlutil.NewMigrator(db)
+	m.AddMigrations(sqlutil.Migration{
+		Version: "userapi: server names populate",
+		Up: func(ctx context.Context, txn *sql.Tx) error {
+			return deltas.UpServerNamesPopulate(ctx, txn, serverName)
+		},
+	})
+	if err = m.Up(base.Context()); err != nil {
+		return nil, err
+	}
+
 	return &shared.Database{
 		AccountDatas:          accountDataTable,
 		Accounts:              accountsTable,
diff --git a/userapi/storage/postgres/threepid_table.go b/userapi/storage/postgres/threepid_table.go
index 11af7616..f41c4312 100644
--- a/userapi/storage/postgres/threepid_table.go
+++ b/userapi/storage/postgres/threepid_table.go
@@ -20,6 +20,7 @@ import (
 
 	"github.com/matrix-org/dendrite/internal/sqlutil"
 	"github.com/matrix-org/dendrite/userapi/storage/tables"
+	"github.com/matrix-org/gomatrixserverlib"
 
 	"github.com/matrix-org/dendrite/clientapi/auth/authtypes"
 )
@@ -33,21 +34,22 @@ CREATE TABLE IF NOT EXISTS userapi_threepids (
 	medium TEXT NOT NULL DEFAULT 'email',
 	-- The localpart of the Matrix user ID associated to this 3PID
 	localpart TEXT NOT NULL,
+	server_name TEXT NOT NULL,
 
 	PRIMARY KEY(threepid, medium)
 );
 
-CREATE INDEX IF NOT EXISTS userapi_threepid_idx ON userapi_threepids(localpart);
+CREATE INDEX IF NOT EXISTS userapi_threepid_idx ON userapi_threepids(localpart, server_name);
 `
 
 const selectLocalpartForThreePIDSQL = "" +
-	"SELECT localpart FROM userapi_threepids WHERE threepid = $1 AND medium = $2"
+	"SELECT localpart, server_name FROM userapi_threepids WHERE threepid = $1 AND medium = $2"
 
 const selectThreePIDsForLocalpartSQL = "" +
-	"SELECT threepid, medium FROM userapi_threepids WHERE localpart = $1"
+	"SELECT threepid, medium FROM userapi_threepids WHERE localpart = $1 AND server_name = $2"
 
 const insertThreePIDSQL = "" +
-	"INSERT INTO userapi_threepids (threepid, medium, localpart) VALUES ($1, $2, $3)"
+	"INSERT INTO userapi_threepids (threepid, medium, localpart, server_name) VALUES ($1, $2, $3, $4)"
 
 const deleteThreePIDSQL = "" +
 	"DELETE FROM userapi_threepids WHERE threepid = $1 AND medium = $2"
@@ -75,19 +77,20 @@ func NewPostgresThreePIDTable(db *sql.DB) (tables.ThreePIDTable, error) {
 
 func (s *threepidStatements) SelectLocalpartForThreePID(
 	ctx context.Context, txn *sql.Tx, threepid string, medium string,
-) (localpart string, err error) {
+) (localpart string, serverName gomatrixserverlib.ServerName, err error) {
 	stmt := sqlutil.TxStmt(txn, s.selectLocalpartForThreePIDStmt)
-	err = stmt.QueryRowContext(ctx, threepid, medium).Scan(&localpart)
+	err = stmt.QueryRowContext(ctx, threepid, medium).Scan(&localpart, &serverName)
 	if err == sql.ErrNoRows {
-		return "", nil
+		return "", "", nil
 	}
 	return
 }
 
 func (s *threepidStatements) SelectThreePIDsForLocalpart(
-	ctx context.Context, localpart string,
+	ctx context.Context,
+	localpart string, serverName gomatrixserverlib.ServerName,
 ) (threepids []authtypes.ThreePID, err error) {
-	rows, err := s.selectThreePIDsForLocalpartStmt.QueryContext(ctx, localpart)
+	rows, err := s.selectThreePIDsForLocalpartStmt.QueryContext(ctx, localpart, serverName)
 	if err != nil {
 		return
 	}
@@ -109,10 +112,11 @@ func (s *threepidStatements) SelectThreePIDsForLocalpart(
 }
 
 func (s *threepidStatements) InsertThreePID(
-	ctx context.Context, txn *sql.Tx, threepid, medium, localpart string,
+	ctx context.Context, txn *sql.Tx, threepid, medium,
+	localpart string, serverName gomatrixserverlib.ServerName,
 ) (err error) {
 	stmt := sqlutil.TxStmt(txn, s.insertThreePIDStmt)
-	_, err = stmt.ExecContext(ctx, threepid, medium, localpart)
+	_, err = stmt.ExecContext(ctx, threepid, medium, localpart, serverName)
 	return
 }
 
diff --git a/userapi/storage/shared/storage.go b/userapi/storage/shared/storage.go
index f8b8d02c..f549dcef 100644
--- a/userapi/storage/shared/storage.go
+++ b/userapi/storage/shared/storage.go
@@ -68,9 +68,10 @@ const (
 // GetAccountByPassword returns the account associated with the given localpart and password.
 // Returns sql.ErrNoRows if no account exists which matches the given localpart.
 func (d *Database) GetAccountByPassword(
-	ctx context.Context, localpart, plaintextPassword string,
+	ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName,
+	plaintextPassword string,
 ) (*api.Account, error) {
-	hash, err := d.Accounts.SelectPasswordHash(ctx, localpart)
+	hash, err := d.Accounts.SelectPasswordHash(ctx, localpart, serverName)
 	if err != nil {
 		return nil, err
 	}
@@ -80,24 +81,27 @@ func (d *Database) GetAccountByPassword(
 	if err := bcrypt.CompareHashAndPassword([]byte(hash), []byte(plaintextPassword)); err != nil {
 		return nil, err
 	}
-	return d.Accounts.SelectAccountByLocalpart(ctx, localpart)
+	return d.Accounts.SelectAccountByLocalpart(ctx, localpart, serverName)
 }
 
 // GetProfileByLocalpart returns the profile associated with the given localpart.
 // Returns sql.ErrNoRows if no profile exists which matches the given localpart.
 func (d *Database) GetProfileByLocalpart(
-	ctx context.Context, localpart string,
+	ctx context.Context,
+	localpart string, serverName gomatrixserverlib.ServerName,
 ) (*authtypes.Profile, error) {
-	return d.Profiles.SelectProfileByLocalpart(ctx, localpart)
+	return d.Profiles.SelectProfileByLocalpart(ctx, localpart, serverName)
 }
 
 // SetAvatarURL updates the avatar URL of the profile associated with the given
 // localpart. Returns an error if something went wrong with the SQL query
 func (d *Database) SetAvatarURL(
-	ctx context.Context, localpart string, avatarURL string,
+	ctx context.Context,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	avatarURL string,
 ) (profile *authtypes.Profile, changed bool, err error) {
 	err = d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
-		profile, changed, err = d.Profiles.SetAvatarURL(ctx, txn, localpart, avatarURL)
+		profile, changed, err = d.Profiles.SetAvatarURL(ctx, txn, localpart, serverName, avatarURL)
 		return err
 	})
 	return
@@ -106,10 +110,12 @@ func (d *Database) SetAvatarURL(
 // SetDisplayName updates the display name of the profile associated with the given
 // localpart. Returns an error if something went wrong with the SQL query
 func (d *Database) SetDisplayName(
-	ctx context.Context, localpart string, displayName string,
+	ctx context.Context,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	displayName string,
 ) (profile *authtypes.Profile, changed bool, err error) {
 	err = d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
-		profile, changed, err = d.Profiles.SetDisplayName(ctx, txn, localpart, displayName)
+		profile, changed, err = d.Profiles.SetDisplayName(ctx, txn, localpart, serverName, displayName)
 		return err
 	})
 	return
@@ -117,14 +123,15 @@ func (d *Database) SetDisplayName(
 
 // SetPassword sets the account password to the given hash.
 func (d *Database) SetPassword(
-	ctx context.Context, localpart, plaintextPassword string,
+	ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName,
+	plaintextPassword string,
 ) error {
 	hash, err := d.hashPassword(plaintextPassword)
 	if err != nil {
 		return err
 	}
 	return d.Writer.Do(nil, nil, func(txn *sql.Tx) error {
-		return d.Accounts.UpdatePassword(ctx, localpart, hash)
+		return d.Accounts.UpdatePassword(ctx, localpart, serverName, hash)
 	})
 }
 
@@ -132,21 +139,22 @@ func (d *Database) SetPassword(
 // for this account. If no password is supplied, the account will be a passwordless account. If the
 // account already exists, it will return nil, ErrUserExists.
 func (d *Database) CreateAccount(
-	ctx context.Context, localpart, plaintextPassword, appserviceID string, accountType api.AccountType,
+	ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName,
+	plaintextPassword, appserviceID string, accountType api.AccountType,
 ) (acc *api.Account, err error) {
 	err = d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
 		// For guest accounts, we create a new numeric local part
 		if accountType == api.AccountTypeGuest {
 			var numLocalpart int64
-			numLocalpart, err = d.Accounts.SelectNewNumericLocalpart(ctx, txn)
+			numLocalpart, err = d.Accounts.SelectNewNumericLocalpart(ctx, txn, serverName)
 			if err != nil {
-				return err
+				return fmt.Errorf("d.Accounts.SelectNewNumericLocalpart: %w", err)
 			}
 			localpart = strconv.FormatInt(numLocalpart, 10)
 			plaintextPassword = ""
 			appserviceID = ""
 		}
-		acc, err = d.createAccount(ctx, txn, localpart, plaintextPassword, appserviceID, accountType)
+		acc, err = d.createAccount(ctx, txn, localpart, serverName, plaintextPassword, appserviceID, accountType)
 		return err
 	})
 	return
@@ -155,7 +163,9 @@ func (d *Database) CreateAccount(
 // WARNING! This function assumes that the relevant mutexes have already
 // been taken out by the caller (e.g. CreateAccount or CreateGuestAccount).
 func (d *Database) createAccount(
-	ctx context.Context, txn *sql.Tx, localpart, plaintextPassword, appserviceID string, accountType api.AccountType,
+	ctx context.Context, txn *sql.Tx,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	plaintextPassword, appserviceID string, accountType api.AccountType,
 ) (*api.Account, error) {
 	var err error
 	var account *api.Account
@@ -167,28 +177,28 @@ func (d *Database) createAccount(
 			return nil, err
 		}
 	}
-	if account, err = d.Accounts.InsertAccount(ctx, txn, localpart, hash, appserviceID, accountType); err != nil {
+	if account, err = d.Accounts.InsertAccount(ctx, txn, localpart, serverName, hash, appserviceID, accountType); err != nil {
 		return nil, sqlutil.ErrUserExists
 	}
-	if err = d.Profiles.InsertProfile(ctx, txn, localpart); err != nil {
-		return nil, err
+	if err = d.Profiles.InsertProfile(ctx, txn, localpart, serverName); err != nil {
+		return nil, fmt.Errorf("d.Profiles.InsertProfile: %w", err)
 	}
-	pushRuleSets := pushrules.DefaultAccountRuleSets(localpart, d.ServerName)
+	pushRuleSets := pushrules.DefaultAccountRuleSets(localpart, serverName)
 	prbs, err := json.Marshal(pushRuleSets)
 	if err != nil {
-		return nil, err
+		return nil, fmt.Errorf("json.Marshal: %w", err)
 	}
-	if err = d.AccountDatas.InsertAccountData(ctx, txn, localpart, "", "m.push_rules", json.RawMessage(prbs)); err != nil {
-		return nil, err
+	if err = d.AccountDatas.InsertAccountData(ctx, txn, localpart, serverName, "", "m.push_rules", json.RawMessage(prbs)); err != nil {
+		return nil, fmt.Errorf("d.AccountDatas.InsertAccountData: %w", err)
 	}
 	return account, nil
 }
 
 func (d *Database) QueryPushRules(
 	ctx context.Context,
-	localpart string,
+	localpart string, serverName gomatrixserverlib.ServerName,
 ) (*pushrules.AccountRuleSets, error) {
-	data, err := d.AccountDatas.SelectAccountDataByType(ctx, localpart, "", "m.push_rules")
+	data, err := d.AccountDatas.SelectAccountDataByType(ctx, localpart, serverName, "", "m.push_rules")
 	if err != nil {
 		return nil, err
 	}
@@ -196,13 +206,13 @@ func (d *Database) QueryPushRules(
 	// If we didn't find any default push rules then we should just generate some
 	// fresh ones.
 	if len(data) == 0 {
-		pushRuleSets := pushrules.DefaultAccountRuleSets(localpart, d.ServerName)
+		pushRuleSets := pushrules.DefaultAccountRuleSets(localpart, serverName)
 		prbs, err := json.Marshal(pushRuleSets)
 		if err != nil {
 			return nil, fmt.Errorf("failed to marshal default push rules: %w", err)
 		}
 		err = d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
-			if dbErr := d.AccountDatas.InsertAccountData(ctx, txn, localpart, "", "m.push_rules", prbs); dbErr != nil {
+			if dbErr := d.AccountDatas.InsertAccountData(ctx, txn, localpart, serverName, "", "m.push_rules", prbs); dbErr != nil {
 				return fmt.Errorf("failed to save default push rules: %w", dbErr)
 			}
 			return nil
@@ -225,22 +235,23 @@ func (d *Database) QueryPushRules(
 // update the corresponding row with the new content
 // Returns a SQL error if there was an issue with the insertion/update
 func (d *Database) SaveAccountData(
-	ctx context.Context, localpart, roomID, dataType string, content json.RawMessage,
+	ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName,
+	roomID, dataType string, content json.RawMessage,
 ) error {
 	return d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
-		return d.AccountDatas.InsertAccountData(ctx, txn, localpart, roomID, dataType, content)
+		return d.AccountDatas.InsertAccountData(ctx, txn, localpart, serverName, roomID, dataType, content)
 	})
 }
 
 // GetAccountData returns account data related to a given localpart
 // If no account data could be found, returns an empty arrays
 // Returns an error if there was an issue with the retrieval
-func (d *Database) GetAccountData(ctx context.Context, localpart string) (
+func (d *Database) GetAccountData(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName) (
 	global map[string]json.RawMessage,
 	rooms map[string]map[string]json.RawMessage,
 	err error,
 ) {
-	return d.AccountDatas.SelectAccountData(ctx, localpart)
+	return d.AccountDatas.SelectAccountData(ctx, localpart, serverName)
 }
 
 // GetAccountDataByType returns account data matching a given
@@ -248,18 +259,19 @@ func (d *Database) GetAccountData(ctx context.Context, localpart string) (
 // If no account data could be found, returns nil
 // Returns an error if there was an issue with the retrieval
 func (d *Database) GetAccountDataByType(
-	ctx context.Context, localpart, roomID, dataType string,
+	ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName,
+	roomID, dataType string,
 ) (data json.RawMessage, err error) {
 	return d.AccountDatas.SelectAccountDataByType(
-		ctx, localpart, roomID, dataType,
+		ctx, localpart, serverName, roomID, dataType,
 	)
 }
 
 // GetNewNumericLocalpart generates and returns a new unused numeric localpart
 func (d *Database) GetNewNumericLocalpart(
-	ctx context.Context,
+	ctx context.Context, serverName gomatrixserverlib.ServerName,
 ) (int64, error) {
-	return d.Accounts.SelectNewNumericLocalpart(ctx, nil)
+	return d.Accounts.SelectNewNumericLocalpart(ctx, nil, serverName)
 }
 
 func (d *Database) hashPassword(plaintext string) (hash string, err error) {
@@ -276,10 +288,12 @@ var Err3PIDInUse = errors.New("this third-party identifier is already in use")
 // If the third-party identifier is already part of an association, returns Err3PIDInUse.
 // Returns an error if there was a problem talking to the database.
 func (d *Database) SaveThreePIDAssociation(
-	ctx context.Context, threepid, localpart, medium string,
+	ctx context.Context, threepid string,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	medium string,
 ) (err error) {
 	return d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
-		user, err := d.ThreePIDs.SelectLocalpartForThreePID(
+		user, _, err := d.ThreePIDs.SelectLocalpartForThreePID(
 			ctx, txn, threepid, medium,
 		)
 		if err != nil {
@@ -290,7 +304,7 @@ func (d *Database) SaveThreePIDAssociation(
 			return Err3PIDInUse
 		}
 
-		return d.ThreePIDs.InsertThreePID(ctx, txn, threepid, medium, localpart)
+		return d.ThreePIDs.InsertThreePID(ctx, txn, threepid, medium, localpart, serverName)
 	})
 }
 
@@ -313,7 +327,7 @@ func (d *Database) RemoveThreePIDAssociation(
 // Returns an error if there was a problem talking to the database.
 func (d *Database) GetLocalpartForThreePID(
 	ctx context.Context, threepid string, medium string,
-) (localpart string, err error) {
+) (localpart string, serverName gomatrixserverlib.ServerName, err error) {
 	return d.ThreePIDs.SelectLocalpartForThreePID(ctx, nil, threepid, medium)
 }
 
@@ -322,16 +336,17 @@ func (d *Database) GetLocalpartForThreePID(
 // If no association is known for this user, returns an empty slice.
 // Returns an error if there was an issue talking to the database.
 func (d *Database) GetThreePIDsForLocalpart(
-	ctx context.Context, localpart string,
+	ctx context.Context,
+	localpart string, serverName gomatrixserverlib.ServerName,
 ) (threepids []authtypes.ThreePID, err error) {
-	return d.ThreePIDs.SelectThreePIDsForLocalpart(ctx, localpart)
+	return d.ThreePIDs.SelectThreePIDsForLocalpart(ctx, localpart, serverName)
 }
 
 // CheckAccountAvailability checks if the username/localpart is already present
 // in the database.
 // If the DB returns sql.ErrNoRows the Localpart isn't taken.
-func (d *Database) CheckAccountAvailability(ctx context.Context, localpart string) (bool, error) {
-	_, err := d.Accounts.SelectAccountByLocalpart(ctx, localpart)
+func (d *Database) CheckAccountAvailability(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName) (bool, error) {
+	_, err := d.Accounts.SelectAccountByLocalpart(ctx, localpart, serverName)
 	if err == sql.ErrNoRows {
 		return true, nil
 	}
@@ -341,12 +356,12 @@ func (d *Database) CheckAccountAvailability(ctx context.Context, localpart strin
 // GetAccountByLocalpart returns the account associated with the given localpart.
 // This function assumes the request is authenticated or the account data is used only internally.
 // Returns sql.ErrNoRows if no account exists which matches the given localpart.
-func (d *Database) GetAccountByLocalpart(ctx context.Context, localpart string,
+func (d *Database) GetAccountByLocalpart(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName,
 ) (*api.Account, error) {
 	// try to get the account with lowercase localpart (majority)
-	acc, err := d.Accounts.SelectAccountByLocalpart(ctx, strings.ToLower(localpart))
+	acc, err := d.Accounts.SelectAccountByLocalpart(ctx, strings.ToLower(localpart), serverName)
 	if err == sql.ErrNoRows {
-		acc, err = d.Accounts.SelectAccountByLocalpart(ctx, localpart) // try with localpart as passed by the request
+		acc, err = d.Accounts.SelectAccountByLocalpart(ctx, localpart, serverName) // try with localpart as passed by the request
 	}
 	return acc, err
 }
@@ -359,20 +374,24 @@ func (d *Database) SearchProfiles(ctx context.Context, searchString string, limi
 }
 
 // DeactivateAccount deactivates the user's account, removing all ability for the user to login again.
-func (d *Database) DeactivateAccount(ctx context.Context, localpart string) (err error) {
+func (d *Database) DeactivateAccount(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName) (err error) {
 	return d.Writer.Do(nil, nil, func(txn *sql.Tx) error {
-		return d.Accounts.DeactivateAccount(ctx, localpart)
+		return d.Accounts.DeactivateAccount(ctx, localpart, serverName)
 	})
 }
 
 // CreateOpenIDToken persists a new token that was issued for OpenID Connect
 func (d *Database) CreateOpenIDToken(
 	ctx context.Context,
-	token, localpart string,
+	token, userID string,
 ) (int64, error) {
+	localpart, domain, err := gomatrixserverlib.SplitID('@', userID)
+	if err != nil {
+		return 0, nil
+	}
 	expiresAtMS := time.Now().UnixNano()/int64(time.Millisecond) + d.OpenIDTokenLifetimeMS
-	err := d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
-		return d.OpenIDTokens.InsertOpenIDToken(ctx, txn, token, localpart, expiresAtMS)
+	err = d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
+		return d.OpenIDTokens.InsertOpenIDToken(ctx, txn, token, localpart, domain, expiresAtMS)
 	})
 	return expiresAtMS, err
 }
@@ -539,16 +558,19 @@ func (d *Database) GetDeviceByAccessToken(
 // GetDeviceByID returns the device matching the given ID.
 // Returns sql.ErrNoRows if no matching device was found.
 func (d *Database) GetDeviceByID(
-	ctx context.Context, localpart, deviceID string,
+	ctx context.Context,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	deviceID string,
 ) (*api.Device, error) {
-	return d.Devices.SelectDeviceByID(ctx, localpart, deviceID)
+	return d.Devices.SelectDeviceByID(ctx, localpart, serverName, deviceID)
 }
 
 // GetDevicesByLocalpart returns the devices matching the given localpart.
 func (d *Database) GetDevicesByLocalpart(
-	ctx context.Context, localpart string,
+	ctx context.Context,
+	localpart string, serverName gomatrixserverlib.ServerName,
 ) ([]api.Device, error) {
-	return d.Devices.SelectDevicesByLocalpart(ctx, nil, localpart, "")
+	return d.Devices.SelectDevicesByLocalpart(ctx, nil, localpart, serverName, "")
 }
 
 func (d *Database) GetDevicesByID(ctx context.Context, deviceIDs []string) ([]api.Device, error) {
@@ -562,18 +584,18 @@ func (d *Database) GetDevicesByID(ctx context.Context, deviceIDs []string) ([]ap
 // If no device ID is given one is generated.
 // Returns the device on success.
 func (d *Database) CreateDevice(
-	ctx context.Context, localpart string, deviceID *string, accessToken string,
-	displayName *string, ipAddr, userAgent string,
+	ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName,
+	deviceID *string, accessToken string, displayName *string, ipAddr, userAgent string,
 ) (dev *api.Device, returnErr error) {
 	if deviceID != nil {
 		returnErr = d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
 			var err error
 			// Revoke existing tokens for this device
-			if err = d.Devices.DeleteDevice(ctx, txn, *deviceID, localpart); err != nil {
+			if err = d.Devices.DeleteDevice(ctx, txn, *deviceID, localpart, serverName); err != nil {
 				return err
 			}
 
-			dev, err = d.Devices.InsertDevice(ctx, txn, *deviceID, localpart, accessToken, displayName, ipAddr, userAgent)
+			dev, err = d.Devices.InsertDevice(ctx, txn, *deviceID, localpart, serverName, accessToken, displayName, ipAddr, userAgent)
 			return err
 		})
 	} else {
@@ -588,7 +610,7 @@ func (d *Database) CreateDevice(
 
 			returnErr = d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
 				var err error
-				dev, err = d.Devices.InsertDevice(ctx, txn, newDeviceID, localpart, accessToken, displayName, ipAddr, userAgent)
+				dev, err = d.Devices.InsertDevice(ctx, txn, newDeviceID, localpart, serverName, accessToken, displayName, ipAddr, userAgent)
 				return err
 			})
 			if returnErr == nil {
@@ -614,10 +636,12 @@ func generateDeviceID() (string, error) {
 // UpdateDevice updates the given device with the display name.
 // Returns SQL error if there are problems and nil on success.
 func (d *Database) UpdateDevice(
-	ctx context.Context, localpart, deviceID string, displayName *string,
+	ctx context.Context,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	deviceID string, displayName *string,
 ) error {
 	return d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
-		return d.Devices.UpdateDeviceName(ctx, txn, localpart, deviceID, displayName)
+		return d.Devices.UpdateDeviceName(ctx, txn, localpart, serverName, deviceID, displayName)
 	})
 }
 
@@ -626,10 +650,12 @@ func (d *Database) UpdateDevice(
 // If the devices don't exist, it will not return an error
 // If something went wrong during the deletion, it will return the SQL error.
 func (d *Database) RemoveDevices(
-	ctx context.Context, localpart string, devices []string,
+	ctx context.Context,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	devices []string,
 ) error {
 	return d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
-		if err := d.Devices.DeleteDevices(ctx, txn, localpart, devices); err != sql.ErrNoRows {
+		if err := d.Devices.DeleteDevices(ctx, txn, localpart, serverName, devices); err != sql.ErrNoRows {
 			return err
 		}
 		return nil
@@ -640,14 +666,16 @@ func (d *Database) RemoveDevices(
 // database matching the given user ID localpart.
 // If something went wrong during the deletion, it will return the SQL error.
 func (d *Database) RemoveAllDevices(
-	ctx context.Context, localpart, exceptDeviceID string,
+	ctx context.Context,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	exceptDeviceID string,
 ) (devices []api.Device, err error) {
 	err = d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
-		devices, err = d.Devices.SelectDevicesByLocalpart(ctx, txn, localpart, exceptDeviceID)
+		devices, err = d.Devices.SelectDevicesByLocalpart(ctx, txn, localpart, serverName, exceptDeviceID)
 		if err != nil {
 			return err
 		}
-		if err := d.Devices.DeleteDevicesByLocalpart(ctx, txn, localpart, exceptDeviceID); err != sql.ErrNoRows {
+		if err := d.Devices.DeleteDevicesByLocalpart(ctx, txn, localpart, serverName, exceptDeviceID); err != sql.ErrNoRows {
 			return err
 		}
 		return nil
@@ -656,9 +684,9 @@ func (d *Database) RemoveAllDevices(
 }
 
 // UpdateDeviceLastSeen updates a last seen timestamp and the ip address.
-func (d *Database) UpdateDeviceLastSeen(ctx context.Context, localpart, deviceID, ipAddr, userAgent string) error {
+func (d *Database) UpdateDeviceLastSeen(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, deviceID, ipAddr, userAgent string) error {
 	return d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
-		return d.Devices.UpdateDeviceLastSeen(ctx, txn, localpart, deviceID, ipAddr, userAgent)
+		return d.Devices.UpdateDeviceLastSeen(ctx, txn, localpart, serverName, deviceID, ipAddr, userAgent)
 	})
 }
 
@@ -706,38 +734,38 @@ func (d *Database) GetLoginTokenDataByToken(ctx context.Context, token string) (
 	return d.LoginTokens.SelectLoginToken(ctx, token)
 }
 
-func (d *Database) InsertNotification(ctx context.Context, localpart, eventID string, pos uint64, tweaks map[string]interface{}, n *api.Notification) error {
+func (d *Database) InsertNotification(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, eventID string, pos uint64, tweaks map[string]interface{}, n *api.Notification) error {
 	return d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
-		return d.Notifications.Insert(ctx, txn, localpart, eventID, pos, pushrules.BoolTweakOr(tweaks, pushrules.HighlightTweak, false), n)
+		return d.Notifications.Insert(ctx, txn, localpart, serverName, eventID, pos, pushrules.BoolTweakOr(tweaks, pushrules.HighlightTweak, false), n)
 	})
 }
 
-func (d *Database) DeleteNotificationsUpTo(ctx context.Context, localpart, roomID string, pos uint64) (affected bool, err error) {
+func (d *Database) DeleteNotificationsUpTo(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, roomID string, pos uint64) (affected bool, err error) {
 	err = d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
-		affected, err = d.Notifications.DeleteUpTo(ctx, txn, localpart, roomID, pos)
+		affected, err = d.Notifications.DeleteUpTo(ctx, txn, localpart, serverName, roomID, pos)
 		return err
 	})
 	return
 }
 
-func (d *Database) SetNotificationsRead(ctx context.Context, localpart, roomID string, pos uint64, b bool) (affected bool, err error) {
+func (d *Database) SetNotificationsRead(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, roomID string, pos uint64, b bool) (affected bool, err error) {
 	err = d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
-		affected, err = d.Notifications.UpdateRead(ctx, txn, localpart, roomID, pos, b)
+		affected, err = d.Notifications.UpdateRead(ctx, txn, localpart, serverName, roomID, pos, b)
 		return err
 	})
 	return
 }
 
-func (d *Database) GetNotifications(ctx context.Context, localpart string, fromID int64, limit int, filter tables.NotificationFilter) ([]*api.Notification, int64, error) {
-	return d.Notifications.Select(ctx, nil, localpart, fromID, limit, filter)
+func (d *Database) GetNotifications(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, fromID int64, limit int, filter tables.NotificationFilter) ([]*api.Notification, int64, error) {
+	return d.Notifications.Select(ctx, nil, localpart, serverName, fromID, limit, filter)
 }
 
-func (d *Database) GetNotificationCount(ctx context.Context, localpart string, filter tables.NotificationFilter) (int64, error) {
-	return d.Notifications.SelectCount(ctx, nil, localpart, filter)
+func (d *Database) GetNotificationCount(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, filter tables.NotificationFilter) (int64, error) {
+	return d.Notifications.SelectCount(ctx, nil, localpart, serverName, filter)
 }
 
-func (d *Database) GetRoomNotificationCounts(ctx context.Context, localpart, roomID string) (total int64, highlight int64, _ error) {
-	return d.Notifications.SelectRoomCounts(ctx, nil, localpart, roomID)
+func (d *Database) GetRoomNotificationCounts(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, roomID string) (total int64, highlight int64, _ error) {
+	return d.Notifications.SelectRoomCounts(ctx, nil, localpart, serverName, roomID)
 }
 
 func (d *Database) DeleteOldNotifications(ctx context.Context) error {
@@ -747,7 +775,8 @@ func (d *Database) DeleteOldNotifications(ctx context.Context) error {
 }
 
 func (d *Database) UpsertPusher(
-	ctx context.Context, p api.Pusher, localpart string,
+	ctx context.Context, p api.Pusher,
+	localpart string, serverName gomatrixserverlib.ServerName,
 ) error {
 	data, err := json.Marshal(p.Data)
 	if err != nil {
@@ -766,25 +795,26 @@ func (d *Database) UpsertPusher(
 			p.ProfileTag,
 			p.Language,
 			string(data),
-			localpart)
+			localpart,
+			serverName)
 	})
 }
 
 // GetPushers returns the pushers matching the given localpart.
 func (d *Database) GetPushers(
-	ctx context.Context, localpart string,
+	ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName,
 ) ([]api.Pusher, error) {
-	return d.Pushers.SelectPushers(ctx, nil, localpart)
+	return d.Pushers.SelectPushers(ctx, nil, localpart, serverName)
 }
 
 // RemovePusher deletes one pusher
 // Invoked when `append` is true and `kind` is null in
 // https://matrix.org/docs/spec/client_server/r0.6.1#post-matrix-client-r0-pushers-set
 func (d *Database) RemovePusher(
-	ctx context.Context, appid, pushkey, localpart string,
+	ctx context.Context, appid, pushkey, localpart string, serverName gomatrixserverlib.ServerName,
 ) error {
 	return d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
-		err := d.Pushers.DeletePusher(ctx, txn, appid, pushkey, localpart)
+		err := d.Pushers.DeletePusher(ctx, txn, appid, pushkey, localpart, serverName)
 		if err == sql.ErrNoRows {
 			return nil
 		}
diff --git a/userapi/storage/sqlite3/account_data_table.go b/userapi/storage/sqlite3/account_data_table.go
index af12decb..2fbdc573 100644
--- a/userapi/storage/sqlite3/account_data_table.go
+++ b/userapi/storage/sqlite3/account_data_table.go
@@ -21,6 +21,7 @@ import (
 
 	"github.com/matrix-org/dendrite/internal/sqlutil"
 	"github.com/matrix-org/dendrite/userapi/storage/tables"
+	"github.com/matrix-org/gomatrixserverlib"
 )
 
 const accountDataSchema = `
@@ -28,27 +29,28 @@ const accountDataSchema = `
 CREATE TABLE IF NOT EXISTS userapi_account_datas (
     -- The Matrix user ID localpart for this account
     localpart TEXT NOT NULL,
+	server_name TEXT NOT NULL,
     -- The room ID for this data (empty string if not specific to a room)
     room_id TEXT,
     -- The account data type
     type TEXT NOT NULL,
     -- The account data content
-    content TEXT NOT NULL,
-
-    PRIMARY KEY(localpart, room_id, type)
+    content TEXT NOT NULL
 );
+
+CREATE UNIQUE INDEX IF NOT EXISTS userapi_account_datas_idx ON userapi_account_datas(localpart, server_name, room_id, type);
 `
 
 const insertAccountDataSQL = `
-	INSERT INTO userapi_account_datas(localpart, room_id, type, content) VALUES($1, $2, $3, $4)
-	ON CONFLICT (localpart, room_id, type) DO UPDATE SET content = $4
+	INSERT INTO userapi_account_datas(localpart, server_name, room_id, type, content) VALUES($1, $2, $3, $4, $5)
+	ON CONFLICT (localpart, server_name, room_id, type) DO UPDATE SET content = $5
 `
 
 const selectAccountDataSQL = "" +
-	"SELECT room_id, type, content FROM userapi_account_datas WHERE localpart = $1"
+	"SELECT room_id, type, content FROM userapi_account_datas WHERE localpart = $1 AND server_name = $2"
 
 const selectAccountDataByTypeSQL = "" +
-	"SELECT content FROM userapi_account_datas WHERE localpart = $1 AND room_id = $2 AND type = $3"
+	"SELECT content FROM userapi_account_datas WHERE localpart = $1 AND server_name = $2 AND room_id = $3 AND type = $4"
 
 type accountDataStatements struct {
 	db                          *sql.DB
@@ -73,20 +75,23 @@ func NewSQLiteAccountDataTable(db *sql.DB) (tables.AccountDataTable, error) {
 }
 
 func (s *accountDataStatements) InsertAccountData(
-	ctx context.Context, txn *sql.Tx, localpart, roomID, dataType string, content json.RawMessage,
+	ctx context.Context, txn *sql.Tx,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	roomID, dataType string, content json.RawMessage,
 ) error {
-	_, err := sqlutil.TxStmt(txn, s.insertAccountDataStmt).ExecContext(ctx, localpart, roomID, dataType, content)
+	_, err := sqlutil.TxStmt(txn, s.insertAccountDataStmt).ExecContext(ctx, localpart, serverName, roomID, dataType, content)
 	return err
 }
 
 func (s *accountDataStatements) SelectAccountData(
-	ctx context.Context, localpart string,
+	ctx context.Context,
+	localpart string, serverName gomatrixserverlib.ServerName,
 ) (
 	/* global */ map[string]json.RawMessage,
 	/* rooms */ map[string]map[string]json.RawMessage,
 	error,
 ) {
-	rows, err := s.selectAccountDataStmt.QueryContext(ctx, localpart)
+	rows, err := s.selectAccountDataStmt.QueryContext(ctx, localpart, serverName)
 	if err != nil {
 		return nil, nil, err
 	}
@@ -117,11 +122,13 @@ func (s *accountDataStatements) SelectAccountData(
 }
 
 func (s *accountDataStatements) SelectAccountDataByType(
-	ctx context.Context, localpart, roomID, dataType string,
+	ctx context.Context,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	roomID, dataType string,
 ) (data json.RawMessage, err error) {
 	var bytes []byte
 	stmt := s.selectAccountDataByTypeStmt
-	if err = stmt.QueryRowContext(ctx, localpart, roomID, dataType).Scan(&bytes); err != nil {
+	if err = stmt.QueryRowContext(ctx, localpart, serverName, roomID, dataType).Scan(&bytes); err != nil {
 		if err == sql.ErrNoRows {
 			return nil, nil
 		}
diff --git a/userapi/storage/sqlite3/accounts_table.go b/userapi/storage/sqlite3/accounts_table.go
index 671c1aa0..f4ebe215 100644
--- a/userapi/storage/sqlite3/accounts_table.go
+++ b/userapi/storage/sqlite3/accounts_table.go
@@ -34,7 +34,8 @@ const accountsSchema = `
 -- Stores data about accounts.
 CREATE TABLE IF NOT EXISTS userapi_accounts (
     -- The Matrix user ID localpart for this account
-    localpart TEXT NOT NULL PRIMARY KEY,
+    localpart TEXT NOT NULL,
+    server_name TEXT NOT NULL,
     -- When this account was first created, as a unix timestamp (ms resolution).
     created_ts BIGINT NOT NULL,
     -- The password hash for this account. Can be NULL if this is a passwordless account.
@@ -48,25 +49,27 @@ CREATE TABLE IF NOT EXISTS userapi_accounts (
     -- TODO:
     -- upgraded_ts, devices, any email reset stuff?
 );
+
+CREATE UNIQUE INDEX IF NOT EXISTS userapi_accounts_idx ON userapi_accounts(localpart, server_name);
 `
 
 const insertAccountSQL = "" +
-	"INSERT INTO userapi_accounts(localpart, created_ts, password_hash, appservice_id, account_type) VALUES ($1, $2, $3, $4, $5)"
+	"INSERT INTO userapi_accounts(localpart, server_name, created_ts, password_hash, appservice_id, account_type) VALUES ($1, $2, $3, $4, $5, $6)"
 
 const updatePasswordSQL = "" +
-	"UPDATE userapi_accounts SET password_hash = $1 WHERE localpart = $2"
+	"UPDATE userapi_accounts SET password_hash = $1 WHERE localpart = $2 AND server_name = $3"
 
 const deactivateAccountSQL = "" +
-	"UPDATE userapi_accounts SET is_deactivated = 1 WHERE localpart = $1"
+	"UPDATE userapi_accounts SET is_deactivated = 1 WHERE localpart = $1 AND server_name = $2"
 
 const selectAccountByLocalpartSQL = "" +
-	"SELECT localpart, appservice_id, account_type FROM userapi_accounts WHERE localpart = $1"
+	"SELECT localpart, server_name, appservice_id, account_type FROM userapi_accounts WHERE localpart = $1 AND server_name = $2"
 
 const selectPasswordHashSQL = "" +
-	"SELECT password_hash FROM userapi_accounts WHERE localpart = $1 AND is_deactivated = 0"
+	"SELECT password_hash FROM userapi_accounts WHERE localpart = $1 AND server_name = $2 AND is_deactivated = 0"
 
 const selectNewNumericLocalpartSQL = "" +
-	"SELECT COALESCE(MAX(CAST(localpart AS INT)), 0) FROM userapi_accounts WHERE CAST(localpart AS INT) <> 0"
+	"SELECT COALESCE(MAX(CAST(localpart AS INT)), 0) FROM userapi_accounts WHERE CAST(localpart AS INT) <> 0 AND server_name = $1"
 
 type accountsStatements struct {
 	db                            *sql.DB
@@ -119,16 +122,17 @@ func NewSQLiteAccountsTable(db *sql.DB, serverName gomatrixserverlib.ServerName)
 // this account will be passwordless. Returns an error if this account already exists. Returns the account
 // on success.
 func (s *accountsStatements) InsertAccount(
-	ctx context.Context, txn *sql.Tx, localpart, hash, appserviceID string, accountType api.AccountType,
+	ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName,
+	hash, appserviceID string, accountType api.AccountType,
 ) (*api.Account, error) {
 	createdTimeMS := time.Now().UnixNano() / 1000000
 	stmt := s.insertAccountStmt
 
 	var err error
 	if accountType != api.AccountTypeAppService {
-		_, err = sqlutil.TxStmt(txn, stmt).ExecContext(ctx, localpart, createdTimeMS, hash, nil, accountType)
+		_, err = sqlutil.TxStmt(txn, stmt).ExecContext(ctx, localpart, serverName, createdTimeMS, hash, nil, accountType)
 	} else {
-		_, err = sqlutil.TxStmt(txn, stmt).ExecContext(ctx, localpart, createdTimeMS, hash, appserviceID, accountType)
+		_, err = sqlutil.TxStmt(txn, stmt).ExecContext(ctx, localpart, serverName, createdTimeMS, hash, appserviceID, accountType)
 	}
 	if err != nil {
 		return nil, err
@@ -136,42 +140,43 @@ func (s *accountsStatements) InsertAccount(
 
 	return &api.Account{
 		Localpart:    localpart,
-		UserID:       userutil.MakeUserID(localpart, s.serverName),
-		ServerName:   s.serverName,
+		UserID:       userutil.MakeUserID(localpart, serverName),
+		ServerName:   serverName,
 		AppServiceID: appserviceID,
 		AccountType:  accountType,
 	}, nil
 }
 
 func (s *accountsStatements) UpdatePassword(
-	ctx context.Context, localpart, passwordHash string,
+	ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName,
+	passwordHash string,
 ) (err error) {
-	_, err = s.updatePasswordStmt.ExecContext(ctx, passwordHash, localpart)
+	_, err = s.updatePasswordStmt.ExecContext(ctx, passwordHash, localpart, serverName)
 	return
 }
 
 func (s *accountsStatements) DeactivateAccount(
-	ctx context.Context, localpart string,
+	ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName,
 ) (err error) {
-	_, err = s.deactivateAccountStmt.ExecContext(ctx, localpart)
+	_, err = s.deactivateAccountStmt.ExecContext(ctx, localpart, serverName)
 	return
 }
 
 func (s *accountsStatements) SelectPasswordHash(
-	ctx context.Context, localpart string,
+	ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName,
 ) (hash string, err error) {
-	err = s.selectPasswordHashStmt.QueryRowContext(ctx, localpart).Scan(&hash)
+	err = s.selectPasswordHashStmt.QueryRowContext(ctx, localpart, serverName).Scan(&hash)
 	return
 }
 
 func (s *accountsStatements) SelectAccountByLocalpart(
-	ctx context.Context, localpart string,
+	ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName,
 ) (*api.Account, error) {
 	var appserviceIDPtr sql.NullString
 	var acc api.Account
 
 	stmt := s.selectAccountByLocalpartStmt
-	err := stmt.QueryRowContext(ctx, localpart).Scan(&acc.Localpart, &appserviceIDPtr, &acc.AccountType)
+	err := stmt.QueryRowContext(ctx, localpart, serverName).Scan(&acc.Localpart, &acc.ServerName, &appserviceIDPtr, &acc.AccountType)
 	if err != nil {
 		if err != sql.ErrNoRows {
 			log.WithError(err).Error("Unable to retrieve user from the db")
@@ -182,20 +187,18 @@ func (s *accountsStatements) SelectAccountByLocalpart(
 		acc.AppServiceID = appserviceIDPtr.String
 	}
 
-	acc.UserID = userutil.MakeUserID(localpart, s.serverName)
-	acc.ServerName = s.serverName
-
+	acc.UserID = userutil.MakeUserID(acc.Localpart, acc.ServerName)
 	return &acc, nil
 }
 
 func (s *accountsStatements) SelectNewNumericLocalpart(
-	ctx context.Context, txn *sql.Tx,
+	ctx context.Context, txn *sql.Tx, serverName gomatrixserverlib.ServerName,
 ) (id int64, err error) {
 	stmt := s.selectNewNumericLocalpartStmt
 	if txn != nil {
 		stmt = sqlutil.TxStmt(txn, stmt)
 	}
-	err = stmt.QueryRowContext(ctx).Scan(&id)
+	err = stmt.QueryRowContext(ctx, serverName).Scan(&id)
 	if err == sql.ErrNoRows {
 		return 1, nil
 	}
diff --git a/userapi/storage/sqlite3/deltas/20200929203058_is_active.go b/userapi/storage/sqlite3/deltas/20200929203058_is_active.go
index 9158cb36..2de85005 100644
--- a/userapi/storage/sqlite3/deltas/20200929203058_is_active.go
+++ b/userapi/storage/sqlite3/deltas/20200929203058_is_active.go
@@ -11,6 +11,7 @@ func UpIsActive(ctx context.Context, tx *sql.Tx) error {
 	ALTER TABLE userapi_accounts RENAME TO userapi_accounts_tmp;
 CREATE TABLE userapi_accounts (
     localpart TEXT NOT NULL PRIMARY KEY,
+	server_name TEXT NOT NULL,
     created_ts BIGINT NOT NULL,
     password_hash TEXT,
     appservice_id TEXT,
diff --git a/userapi/storage/sqlite3/deltas/20201001204705_last_seen_ts_ip.go b/userapi/storage/sqlite3/deltas/20201001204705_last_seen_ts_ip.go
index a9224db6..636ce4ef 100644
--- a/userapi/storage/sqlite3/deltas/20201001204705_last_seen_ts_ip.go
+++ b/userapi/storage/sqlite3/deltas/20201001204705_last_seen_ts_ip.go
@@ -14,6 +14,7 @@ func UpLastSeenTSIP(ctx context.Context, tx *sql.Tx) error {
         session_id INTEGER,
         device_id TEXT ,
         localpart TEXT ,
+		server_name TEXT NOT NULL,
         created_ts BIGINT,
         display_name TEXT,
         last_seen_ts BIGINT,
diff --git a/userapi/storage/sqlite3/deltas/2022021012490600_add_account_type.go b/userapi/storage/sqlite3/deltas/2022021012490600_add_account_type.go
index 230bc143..471e496c 100644
--- a/userapi/storage/sqlite3/deltas/2022021012490600_add_account_type.go
+++ b/userapi/storage/sqlite3/deltas/2022021012490600_add_account_type.go
@@ -12,6 +12,7 @@ func UpAddAccountType(ctx context.Context, tx *sql.Tx) error {
 	_, err := tx.ExecContext(ctx, `ALTER TABLE userapi_accounts RENAME TO userapi_accounts_tmp;
 CREATE TABLE userapi_accounts (
     localpart TEXT NOT NULL PRIMARY KEY,
+	server_name TEXT NOT NULL,
     created_ts BIGINT NOT NULL,
     password_hash TEXT,
     appservice_id TEXT,
diff --git a/userapi/storage/sqlite3/deltas/2022110411000000_server_names.go b/userapi/storage/sqlite3/deltas/2022110411000000_server_names.go
new file mode 100644
index 00000000..c11ea684
--- /dev/null
+++ b/userapi/storage/sqlite3/deltas/2022110411000000_server_names.go
@@ -0,0 +1,108 @@
+package deltas
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+	"strings"
+
+	"github.com/lib/pq"
+	"github.com/matrix-org/gomatrixserverlib"
+	"github.com/sirupsen/logrus"
+)
+
+var serverNamesTables = []string{
+	"userapi_accounts",
+	"userapi_account_datas",
+	"userapi_devices",
+	"userapi_notifications",
+	"userapi_openid_tokens",
+	"userapi_profiles",
+	"userapi_pushers",
+	"userapi_threepids",
+}
+
+// These tables have a PRIMARY KEY constraint which we need to drop so
+// that we can recreate a new unique index that contains the server name.
+var serverNamesDropPK = []string{
+	"userapi_accounts",
+	"userapi_account_datas",
+	"userapi_profiles",
+}
+
+// These indices are out of date so let's drop them. They will get recreated
+// automatically.
+var serverNamesDropIndex = []string{
+	"userapi_pusher_localpart_idx",
+	"userapi_pusher_app_id_pushkey_localpart_idx",
+}
+
+// I know what you're thinking: you're wondering "why doesn't this use $1
+// and pass variadic parameters to ExecContext?" — the answer is because
+// PostgreSQL doesn't expect the table name to be specified as a substituted
+// argument in that way so it results in a syntax error in the query.
+
+func UpServerNames(ctx context.Context, tx *sql.Tx, serverName gomatrixserverlib.ServerName) error {
+	for _, table := range serverNamesTables {
+		q := fmt.Sprintf(
+			"SELECT COUNT(name) FROM sqlite_schema WHERE type='table' AND name=%s;",
+			pq.QuoteIdentifier(table),
+		)
+		var c int
+		if err := tx.QueryRowContext(ctx, q).Scan(&c); err != nil || c == 0 {
+			continue
+		}
+		q = fmt.Sprintf(
+			"SELECT COUNT(*) FROM pragma_table_info(%s) WHERE name='server_name'",
+			pq.QuoteIdentifier(table),
+		)
+		if err := tx.QueryRowContext(ctx, q).Scan(&c); err != nil || c == 1 {
+			logrus.Infof("Table %s already has column, skipping", table)
+			continue
+		}
+		if c == 0 {
+			q = fmt.Sprintf(
+				"ALTER TABLE %s ADD COLUMN server_name TEXT NOT NULL DEFAULT '';",
+				pq.QuoteIdentifier(table),
+			)
+			if _, err := tx.ExecContext(ctx, q); err != nil {
+				return fmt.Errorf("add server name to %q error: %w", table, err)
+			}
+		}
+	}
+	for _, table := range serverNamesDropPK {
+		q := fmt.Sprintf(
+			"SELECT COUNT(name), sql FROM sqlite_schema WHERE type='table' AND name=%s;",
+			pq.QuoteIdentifier(table),
+		)
+		var c int
+		var sql string
+		if err := tx.QueryRowContext(ctx, q).Scan(&c, &sql); err != nil || c == 0 {
+			continue
+		}
+		q = fmt.Sprintf(`
+			%s; -- create temporary table
+			INSERT INTO %s SELECT * FROM %s; -- copy data
+			DROP TABLE %s; -- drop original table
+			ALTER TABLE %s RENAME TO %s; -- rename new table
+		`,
+			strings.Replace(sql, table, table+"_tmp", 1), // create temporary table
+			table+"_tmp", table, // copy data
+			table,               // drop original table
+			table+"_tmp", table, // rename new table
+		)
+		if _, err := tx.ExecContext(ctx, q); err != nil {
+			return fmt.Errorf("drop PK from %q error: %w", table, err)
+		}
+	}
+	for _, index := range serverNamesDropIndex {
+		q := fmt.Sprintf(
+			"DROP INDEX IF EXISTS %s;",
+			pq.QuoteIdentifier(index),
+		)
+		if _, err := tx.ExecContext(ctx, q); err != nil {
+			return fmt.Errorf("drop index %q error: %w", index, err)
+		}
+	}
+	return nil
+}
diff --git a/userapi/storage/sqlite3/deltas/2022110411000001_server_names.go b/userapi/storage/sqlite3/deltas/2022110411000001_server_names.go
new file mode 100644
index 00000000..04a47fa7
--- /dev/null
+++ b/userapi/storage/sqlite3/deltas/2022110411000001_server_names.go
@@ -0,0 +1,28 @@
+package deltas
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+
+	"github.com/lib/pq"
+	"github.com/matrix-org/gomatrixserverlib"
+)
+
+// I know what you're thinking: you're wondering "why doesn't this use $1
+// and pass variadic parameters to ExecContext?" — the answer is because
+// PostgreSQL doesn't expect the table name to be specified as a substituted
+// argument in that way so it results in a syntax error in the query.
+
+func UpServerNamesPopulate(ctx context.Context, tx *sql.Tx, serverName gomatrixserverlib.ServerName) error {
+	for _, table := range serverNamesTables {
+		q := fmt.Sprintf(
+			"UPDATE %s SET server_name = %s WHERE server_name = '';",
+			pq.QuoteIdentifier(table), pq.QuoteLiteral(string(serverName)),
+		)
+		if _, err := tx.ExecContext(ctx, q); err != nil {
+			return fmt.Errorf("write server names to %q error: %w", table, err)
+		}
+	}
+	return nil
+}
diff --git a/userapi/storage/sqlite3/devices_table.go b/userapi/storage/sqlite3/devices_table.go
index e53a0806..c5db34bd 100644
--- a/userapi/storage/sqlite3/devices_table.go
+++ b/userapi/storage/sqlite3/devices_table.go
@@ -40,49 +40,50 @@ CREATE TABLE IF NOT EXISTS userapi_devices (
     session_id INTEGER,
     device_id TEXT ,
     localpart TEXT ,
+	server_name TEXT NOT NULL,
     created_ts BIGINT,
     display_name TEXT,
     last_seen_ts BIGINT,
     ip TEXT,
     user_agent TEXT,
 
-		UNIQUE (localpart, device_id)
+	UNIQUE (localpart, server_name, device_id)
 );
 `
 
 const insertDeviceSQL = "" +
-	"INSERT INTO userapi_devices (device_id, localpart, access_token, created_ts, display_name, session_id, last_seen_ts, ip, user_agent)" +
-	" VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9)"
+	"INSERT INTO userapi_devices (device_id, localpart, server_name, access_token, created_ts, display_name, session_id, last_seen_ts, ip, user_agent)" +
+	" VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10)"
 
 const selectDevicesCountSQL = "" +
 	"SELECT COUNT(access_token) FROM userapi_devices"
 
 const selectDeviceByTokenSQL = "" +
-	"SELECT session_id, device_id, localpart FROM userapi_devices WHERE access_token = $1"
+	"SELECT session_id, device_id, localpart, server_name FROM userapi_devices WHERE access_token = $1"
 
 const selectDeviceByIDSQL = "" +
-	"SELECT display_name, last_seen_ts, ip FROM userapi_devices WHERE localpart = $1 and device_id = $2"
+	"SELECT display_name, last_seen_ts, ip FROM userapi_devices WHERE localpart = $1 AND server_name = $2 AND device_id = $3"
 
 const selectDevicesByLocalpartSQL = "" +
-	"SELECT device_id, display_name, last_seen_ts, ip, user_agent FROM userapi_devices WHERE localpart = $1 AND device_id != $2 ORDER BY last_seen_ts DESC"
+	"SELECT device_id, display_name, last_seen_ts, ip, user_agent FROM userapi_devices WHERE localpart = $1 AND server_name = $2 AND device_id != $3 ORDER BY last_seen_ts DESC"
 
 const updateDeviceNameSQL = "" +
-	"UPDATE userapi_devices SET display_name = $1 WHERE localpart = $2 AND device_id = $3"
+	"UPDATE userapi_devices SET display_name = $1 WHERE localpart = $2 AND server_name = $3 AND device_id = $4"
 
 const deleteDeviceSQL = "" +
-	"DELETE FROM userapi_devices WHERE device_id = $1 AND localpart = $2"
+	"DELETE FROM userapi_devices WHERE device_id = $1 AND localpart = $2 AND server_name = $3"
 
 const deleteDevicesByLocalpartSQL = "" +
-	"DELETE FROM userapi_devices WHERE localpart = $1 AND device_id != $2"
+	"DELETE FROM userapi_devices WHERE localpart = $1 AND server_name = $2 AND device_id != $3"
 
 const deleteDevicesSQL = "" +
-	"DELETE FROM userapi_devices WHERE localpart = $1 AND device_id IN ($2)"
+	"DELETE FROM userapi_devices WHERE localpart = $1 AND server_name = $2 AND device_id IN ($3)"
 
 const selectDevicesByIDSQL = "" +
-	"SELECT device_id, localpart, display_name, last_seen_ts FROM userapi_devices WHERE device_id IN ($1) ORDER BY last_seen_ts DESC"
+	"SELECT device_id, localpart, server_name, display_name, last_seen_ts FROM userapi_devices WHERE device_id IN ($1) ORDER BY last_seen_ts DESC"
 
 const updateDeviceLastSeen = "" +
-	"UPDATE userapi_devices SET last_seen_ts = $1, ip = $2, user_agent = $3 WHERE localpart = $4 AND device_id = $5"
+	"UPDATE userapi_devices SET last_seen_ts = $1, ip = $2, user_agent = $3 WHERE localpart = $4 AND server_name = $5 AND device_id = $6"
 
 type devicesStatements struct {
 	db                           *sql.DB
@@ -135,8 +136,9 @@ func NewSQLiteDevicesTable(db *sql.DB, serverName gomatrixserverlib.ServerName)
 // Returns an error if the user already has a device with the given device ID.
 // Returns the device on success.
 func (s *devicesStatements) InsertDevice(
-	ctx context.Context, txn *sql.Tx, id, localpart, accessToken string,
-	displayName *string, ipAddr, userAgent string,
+	ctx context.Context, txn *sql.Tx, id string,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	accessToken string, displayName *string, ipAddr, userAgent string,
 ) (*api.Device, error) {
 	createdTimeMS := time.Now().UnixNano() / 1000000
 	var sessionID int64
@@ -146,12 +148,12 @@ func (s *devicesStatements) InsertDevice(
 		return nil, err
 	}
 	sessionID++
-	if _, err := insertStmt.ExecContext(ctx, id, localpart, accessToken, createdTimeMS, displayName, sessionID, createdTimeMS, ipAddr, userAgent); err != nil {
+	if _, err := insertStmt.ExecContext(ctx, id, localpart, serverName, accessToken, createdTimeMS, displayName, sessionID, createdTimeMS, ipAddr, userAgent); err != nil {
 		return nil, err
 	}
 	return &api.Device{
 		ID:          id,
-		UserID:      userutil.MakeUserID(localpart, s.serverName),
+		UserID:      userutil.MakeUserID(localpart, serverName),
 		AccessToken: accessToken,
 		SessionID:   sessionID,
 		LastSeenTS:  createdTimeMS,
@@ -161,44 +163,52 @@ func (s *devicesStatements) InsertDevice(
 }
 
 func (s *devicesStatements) DeleteDevice(
-	ctx context.Context, txn *sql.Tx, id, localpart string,
+	ctx context.Context, txn *sql.Tx, id string,
+	localpart string, serverName gomatrixserverlib.ServerName,
 ) error {
 	stmt := sqlutil.TxStmt(txn, s.deleteDeviceStmt)
-	_, err := stmt.ExecContext(ctx, id, localpart)
+	_, err := stmt.ExecContext(ctx, id, localpart, serverName)
 	return err
 }
 
 func (s *devicesStatements) DeleteDevices(
-	ctx context.Context, txn *sql.Tx, localpart string, devices []string,
+	ctx context.Context, txn *sql.Tx,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	devices []string,
 ) error {
-	orig := strings.Replace(deleteDevicesSQL, "($2)", sqlutil.QueryVariadicOffset(len(devices), 1), 1)
+	orig := strings.Replace(deleteDevicesSQL, "($3)", sqlutil.QueryVariadicOffset(len(devices), 2), 1)
 	prep, err := s.db.Prepare(orig)
 	if err != nil {
 		return err
 	}
 	stmt := sqlutil.TxStmt(txn, prep)
-	params := make([]interface{}, len(devices)+1)
+	params := make([]interface{}, len(devices)+2)
 	params[0] = localpart
+	params[1] = serverName
 	for i, v := range devices {
-		params[i+1] = v
+		params[i+2] = v
 	}
 	_, err = stmt.ExecContext(ctx, params...)
 	return err
 }
 
 func (s *devicesStatements) DeleteDevicesByLocalpart(
-	ctx context.Context, txn *sql.Tx, localpart, exceptDeviceID string,
+	ctx context.Context, txn *sql.Tx,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	exceptDeviceID string,
 ) error {
 	stmt := sqlutil.TxStmt(txn, s.deleteDevicesByLocalpartStmt)
-	_, err := stmt.ExecContext(ctx, localpart, exceptDeviceID)
+	_, err := stmt.ExecContext(ctx, localpart, serverName, exceptDeviceID)
 	return err
 }
 
 func (s *devicesStatements) UpdateDeviceName(
-	ctx context.Context, txn *sql.Tx, localpart, deviceID string, displayName *string,
+	ctx context.Context, txn *sql.Tx,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	deviceID string, displayName *string,
 ) error {
 	stmt := sqlutil.TxStmt(txn, s.updateDeviceNameStmt)
-	_, err := stmt.ExecContext(ctx, displayName, localpart, deviceID)
+	_, err := stmt.ExecContext(ctx, displayName, localpart, serverName, deviceID)
 	return err
 }
 
@@ -207,10 +217,11 @@ func (s *devicesStatements) SelectDeviceByToken(
 ) (*api.Device, error) {
 	var dev api.Device
 	var localpart string
+	var serverName gomatrixserverlib.ServerName
 	stmt := s.selectDeviceByTokenStmt
-	err := stmt.QueryRowContext(ctx, accessToken).Scan(&dev.SessionID, &dev.ID, &localpart)
+	err := stmt.QueryRowContext(ctx, accessToken).Scan(&dev.SessionID, &dev.ID, &localpart, &serverName)
 	if err == nil {
-		dev.UserID = userutil.MakeUserID(localpart, s.serverName)
+		dev.UserID = userutil.MakeUserID(localpart, serverName)
 		dev.AccessToken = accessToken
 	}
 	return &dev, err
@@ -219,16 +230,18 @@ func (s *devicesStatements) SelectDeviceByToken(
 // selectDeviceByID retrieves a device from the database with the given user
 // localpart and deviceID
 func (s *devicesStatements) SelectDeviceByID(
-	ctx context.Context, localpart, deviceID string,
+	ctx context.Context,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	deviceID string,
 ) (*api.Device, error) {
 	var dev api.Device
 	var displayName, ip sql.NullString
 	stmt := s.selectDeviceByIDStmt
 	var lastseenTS sql.NullInt64
-	err := stmt.QueryRowContext(ctx, localpart, deviceID).Scan(&displayName, &lastseenTS, &ip)
+	err := stmt.QueryRowContext(ctx, localpart, serverName, deviceID).Scan(&displayName, &lastseenTS, &ip)
 	if err == nil {
 		dev.ID = deviceID
-		dev.UserID = userutil.MakeUserID(localpart, s.serverName)
+		dev.UserID = userutil.MakeUserID(localpart, serverName)
 		if displayName.Valid {
 			dev.DisplayName = displayName.String
 		}
@@ -243,10 +256,12 @@ func (s *devicesStatements) SelectDeviceByID(
 }
 
 func (s *devicesStatements) SelectDevicesByLocalpart(
-	ctx context.Context, txn *sql.Tx, localpart, exceptDeviceID string,
+	ctx context.Context, txn *sql.Tx,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	exceptDeviceID string,
 ) ([]api.Device, error) {
 	devices := []api.Device{}
-	rows, err := sqlutil.TxStmt(txn, s.selectDevicesByLocalpartStmt).QueryContext(ctx, localpart, exceptDeviceID)
+	rows, err := sqlutil.TxStmt(txn, s.selectDevicesByLocalpartStmt).QueryContext(ctx, localpart, serverName, exceptDeviceID)
 
 	if err != nil {
 		return devices, err
@@ -276,7 +291,7 @@ func (s *devicesStatements) SelectDevicesByLocalpart(
 			dev.UserAgent = useragent.String
 		}
 
-		dev.UserID = userutil.MakeUserID(localpart, s.serverName)
+		dev.UserID = userutil.MakeUserID(localpart, serverName)
 		devices = append(devices, dev)
 	}
 
@@ -298,10 +313,11 @@ func (s *devicesStatements) SelectDevicesByID(ctx context.Context, deviceIDs []s
 	var devices []api.Device
 	var dev api.Device
 	var localpart string
+	var serverName gomatrixserverlib.ServerName
 	var displayName sql.NullString
 	var lastseents sql.NullInt64
 	for rows.Next() {
-		if err := rows.Scan(&dev.ID, &localpart, &displayName, &lastseents); err != nil {
+		if err := rows.Scan(&dev.ID, &localpart, &serverName, &displayName, &lastseents); err != nil {
 			return nil, err
 		}
 		if displayName.Valid {
@@ -310,15 +326,15 @@ func (s *devicesStatements) SelectDevicesByID(ctx context.Context, deviceIDs []s
 		if lastseents.Valid {
 			dev.LastSeenTS = lastseents.Int64
 		}
-		dev.UserID = userutil.MakeUserID(localpart, s.serverName)
+		dev.UserID = userutil.MakeUserID(localpart, serverName)
 		devices = append(devices, dev)
 	}
 	return devices, rows.Err()
 }
 
-func (s *devicesStatements) UpdateDeviceLastSeen(ctx context.Context, txn *sql.Tx, localpart, deviceID, ipAddr, userAgent string) error {
+func (s *devicesStatements) UpdateDeviceLastSeen(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, deviceID, ipAddr, userAgent string) error {
 	lastSeenTs := time.Now().UnixNano() / 1000000
 	stmt := sqlutil.TxStmt(txn, s.updateDeviceLastSeenStmt)
-	_, err := stmt.ExecContext(ctx, lastSeenTs, ipAddr, userAgent, localpart, deviceID)
+	_, err := stmt.ExecContext(ctx, lastSeenTs, ipAddr, userAgent, localpart, serverName, deviceID)
 	return err
 }
diff --git a/userapi/storage/sqlite3/notifications_table.go b/userapi/storage/sqlite3/notifications_table.go
index a35ec7be..ef39d027 100644
--- a/userapi/storage/sqlite3/notifications_table.go
+++ b/userapi/storage/sqlite3/notifications_table.go
@@ -43,6 +43,7 @@ const notificationSchema = `
 CREATE TABLE IF NOT EXISTS userapi_notifications (
     id INTEGER PRIMARY KEY AUTOINCREMENT,
 	localpart TEXT NOT NULL,
+	server_name TEXT NOT NULL,
 	room_id TEXT NOT NULL,
 	event_id TEXT NOT NULL,
 	stream_pos BIGINT NOT NULL,
@@ -52,33 +53,33 @@ CREATE TABLE IF NOT EXISTS userapi_notifications (
     read BOOLEAN NOT NULL DEFAULT FALSE
 );
 
-CREATE INDEX IF NOT EXISTS userapi_notification_localpart_room_id_event_id_idx ON userapi_notifications(localpart, room_id, event_id);
-CREATE INDEX IF NOT EXISTS userapi_notification_localpart_room_id_id_idx ON userapi_notifications(localpart, room_id, id);
-CREATE INDEX IF NOT EXISTS userapi_notification_localpart_id_idx ON userapi_notifications(localpart, id);
+CREATE INDEX IF NOT EXISTS userapi_notification_localpart_room_id_event_id_idx ON userapi_notifications(localpart, server_name, room_id, event_id);
+CREATE INDEX IF NOT EXISTS userapi_notification_localpart_room_id_id_idx ON userapi_notifications(localpart, server_name, room_id, id);
+CREATE INDEX IF NOT EXISTS userapi_notification_localpart_id_idx ON userapi_notifications(localpart, server_name, id);
 `
 
 const insertNotificationSQL = "" +
-	"INSERT INTO userapi_notifications (localpart, room_id, event_id, stream_pos, ts_ms, highlight, notification_json) VALUES ($1, $2, $3, $4, $5, $6, $7)"
+	"INSERT INTO userapi_notifications (localpart, server_name, room_id, event_id, stream_pos, ts_ms, highlight, notification_json) VALUES ($1, $2, $3, $4, $5, $6, $7, $8)"
 
 const deleteNotificationsUpToSQL = "" +
-	"DELETE FROM userapi_notifications WHERE localpart = $1 AND room_id = $2 AND stream_pos <= $3"
+	"DELETE FROM userapi_notifications WHERE localpart = $1 AND server_name = $2 AND room_id = $3 AND stream_pos <= $4"
 
 const updateNotificationReadSQL = "" +
-	"UPDATE userapi_notifications SET read = $1 WHERE localpart = $2 AND room_id = $3 AND stream_pos <= $4 AND read <> $1"
+	"UPDATE userapi_notifications SET read = $1 WHERE localpart = $2 AND server_name = $3 AND room_id = $4 AND stream_pos <= $5 AND read <> $1"
 
 const selectNotificationSQL = "" +
-	"SELECT id, room_id, ts_ms, read, notification_json FROM userapi_notifications WHERE localpart = $1 AND id > $2 AND (" +
-	"(($3 & 1) <> 0 AND highlight) OR (($3 & 2) <> 0 AND NOT highlight)" +
-	") AND NOT read ORDER BY localpart, id LIMIT $4"
+	"SELECT id, room_id, ts_ms, read, notification_json FROM userapi_notifications WHERE localpart = $1 AND server_name = $2 AND id > $3 AND (" +
+	"(($4 & 1) <> 0 AND highlight) OR (($4 & 2) <> 0 AND NOT highlight)" +
+	") AND NOT read ORDER BY localpart, id LIMIT $5"
 
 const selectNotificationCountSQL = "" +
-	"SELECT COUNT(*) FROM userapi_notifications WHERE localpart = $1 AND (" +
-	"(($2 & 1) <> 0 AND highlight) OR (($2 & 2) <> 0 AND NOT highlight)" +
+	"SELECT COUNT(*) FROM userapi_notifications WHERE localpart = $1 AND server_name = $2 AND (" +
+	"(($3 & 1) <> 0 AND highlight) OR (($3 & 2) <> 0 AND NOT highlight)" +
 	") AND NOT read"
 
 const selectRoomNotificationCountsSQL = "" +
 	"SELECT COUNT(*), COUNT(*) FILTER (WHERE highlight) FROM userapi_notifications " +
-	"WHERE localpart = $1 AND room_id = $2 AND NOT read"
+	"WHERE localpart = $1 AND server_name = $2 AND room_id = $3 AND NOT read"
 
 const cleanNotificationsSQL = "" +
 	"DELETE FROM userapi_notifications WHERE" +
@@ -111,7 +112,7 @@ func (s *notificationsStatements) Clean(ctx context.Context, txn *sql.Tx) error
 }
 
 // Insert inserts a notification into the database.
-func (s *notificationsStatements) Insert(ctx context.Context, txn *sql.Tx, localpart, eventID string, pos uint64, highlight bool, n *api.Notification) error {
+func (s *notificationsStatements) Insert(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, eventID string, pos uint64, highlight bool, n *api.Notification) error {
 	roomID, tsMS := n.RoomID, n.TS
 	nn := *n
 	// Clears out fields that have their own columns to (1) shrink the
@@ -122,13 +123,13 @@ func (s *notificationsStatements) Insert(ctx context.Context, txn *sql.Tx, local
 	if err != nil {
 		return err
 	}
-	_, err = sqlutil.TxStmt(txn, s.insertStmt).ExecContext(ctx, localpart, roomID, eventID, pos, tsMS, highlight, string(bs))
+	_, err = sqlutil.TxStmt(txn, s.insertStmt).ExecContext(ctx, localpart, serverName, roomID, eventID, pos, tsMS, highlight, string(bs))
 	return err
 }
 
 // DeleteUpTo deletes all previous notifications, up to and including the event.
-func (s *notificationsStatements) DeleteUpTo(ctx context.Context, txn *sql.Tx, localpart, roomID string, pos uint64) (affected bool, _ error) {
-	res, err := sqlutil.TxStmt(txn, s.deleteUpToStmt).ExecContext(ctx, localpart, roomID, pos)
+func (s *notificationsStatements) DeleteUpTo(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, roomID string, pos uint64) (affected bool, _ error) {
+	res, err := sqlutil.TxStmt(txn, s.deleteUpToStmt).ExecContext(ctx, localpart, serverName, roomID, pos)
 	if err != nil {
 		return false, err
 	}
@@ -141,8 +142,8 @@ func (s *notificationsStatements) DeleteUpTo(ctx context.Context, txn *sql.Tx, l
 }
 
 // UpdateRead updates the "read" value for an event.
-func (s *notificationsStatements) UpdateRead(ctx context.Context, txn *sql.Tx, localpart, roomID string, pos uint64, v bool) (affected bool, _ error) {
-	res, err := sqlutil.TxStmt(txn, s.updateReadStmt).ExecContext(ctx, v, localpart, roomID, pos)
+func (s *notificationsStatements) UpdateRead(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, roomID string, pos uint64, v bool) (affected bool, _ error) {
+	res, err := sqlutil.TxStmt(txn, s.updateReadStmt).ExecContext(ctx, v, localpart, serverName, roomID, pos)
 	if err != nil {
 		return false, err
 	}
@@ -154,8 +155,8 @@ func (s *notificationsStatements) UpdateRead(ctx context.Context, txn *sql.Tx, l
 	return nrows > 0, nil
 }
 
-func (s *notificationsStatements) Select(ctx context.Context, txn *sql.Tx, localpart string, fromID int64, limit int, filter tables.NotificationFilter) ([]*api.Notification, int64, error) {
-	rows, err := sqlutil.TxStmt(txn, s.selectStmt).QueryContext(ctx, localpart, fromID, uint32(filter), limit)
+func (s *notificationsStatements) Select(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, fromID int64, limit int, filter tables.NotificationFilter) ([]*api.Notification, int64, error) {
+	rows, err := sqlutil.TxStmt(txn, s.selectStmt).QueryContext(ctx, localpart, serverName, fromID, uint32(filter), limit)
 
 	if err != nil {
 		return nil, 0, err
@@ -197,12 +198,12 @@ func (s *notificationsStatements) Select(ctx context.Context, txn *sql.Tx, local
 	return notifs, maxID, rows.Err()
 }
 
-func (s *notificationsStatements) SelectCount(ctx context.Context, txn *sql.Tx, localpart string, filter tables.NotificationFilter) (count int64, err error) {
-	err = sqlutil.TxStmt(txn, s.selectCountStmt).QueryRowContext(ctx, localpart, uint32(filter)).Scan(&count)
+func (s *notificationsStatements) SelectCount(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, filter tables.NotificationFilter) (count int64, err error) {
+	err = sqlutil.TxStmt(txn, s.selectCountStmt).QueryRowContext(ctx, localpart, serverName, uint32(filter)).Scan(&count)
 	return
 }
 
-func (s *notificationsStatements) SelectRoomCounts(ctx context.Context, txn *sql.Tx, localpart, roomID string) (total int64, highlight int64, err error) {
-	err = sqlutil.TxStmt(txn, s.selectRoomCountsStmt).QueryRowContext(ctx, localpart, roomID).Scan(&total, &highlight)
+func (s *notificationsStatements) SelectRoomCounts(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, roomID string) (total int64, highlight int64, err error) {
+	err = sqlutil.TxStmt(txn, s.selectRoomCountsStmt).QueryRowContext(ctx, localpart, serverName, roomID).Scan(&total, &highlight)
 	return
 }
diff --git a/userapi/storage/sqlite3/openid_table.go b/userapi/storage/sqlite3/openid_table.go
index 875f1a9a..f0642974 100644
--- a/userapi/storage/sqlite3/openid_table.go
+++ b/userapi/storage/sqlite3/openid_table.go
@@ -3,6 +3,7 @@ package sqlite3
 import (
 	"context"
 	"database/sql"
+	"fmt"
 
 	"github.com/matrix-org/dendrite/internal/sqlutil"
 	"github.com/matrix-org/dendrite/userapi/api"
@@ -18,16 +19,17 @@ CREATE TABLE IF NOT EXISTS userapi_openid_tokens (
 	token TEXT NOT NULL PRIMARY KEY,
     -- The Matrix user ID for this account
 	localpart TEXT NOT NULL,
+	server_name TEXT NOT NULL,
 	-- When the token expires, as a unix timestamp (ms resolution).
 	token_expires_at_ms BIGINT NOT NULL
 );
 `
 
 const insertOpenIDTokenSQL = "" +
-	"INSERT INTO userapi_openid_tokens(token, localpart, token_expires_at_ms) VALUES ($1, $2, $3)"
+	"INSERT INTO userapi_openid_tokens(token, localpart, server_name, token_expires_at_ms) VALUES ($1, $2, $3, $4)"
 
 const selectOpenIDTokenSQL = "" +
-	"SELECT localpart, token_expires_at_ms FROM userapi_openid_tokens WHERE token = $1"
+	"SELECT localpart, server_name, token_expires_at_ms FROM userapi_openid_tokens WHERE token = $1"
 
 type openIDTokenStatements struct {
 	db              *sql.DB
@@ -56,11 +58,11 @@ func NewSQLiteOpenIDTable(db *sql.DB, serverName gomatrixserverlib.ServerName) (
 func (s *openIDTokenStatements) InsertOpenIDToken(
 	ctx context.Context,
 	txn *sql.Tx,
-	token, localpart string,
+	token, localpart string, serverName gomatrixserverlib.ServerName,
 	expiresAtMS int64,
 ) (err error) {
 	stmt := sqlutil.TxStmt(txn, s.insertTokenStmt)
-	_, err = stmt.ExecContext(ctx, token, localpart, expiresAtMS)
+	_, err = stmt.ExecContext(ctx, token, localpart, serverName, expiresAtMS)
 	return
 }
 
@@ -71,10 +73,13 @@ func (s *openIDTokenStatements) SelectOpenIDTokenAtrributes(
 	token string,
 ) (*api.OpenIDTokenAttributes, error) {
 	var openIDTokenAttrs api.OpenIDTokenAttributes
+	var localpart string
+	var serverName gomatrixserverlib.ServerName
 	err := s.selectTokenStmt.QueryRowContext(ctx, token).Scan(
-		&openIDTokenAttrs.UserID,
+		&localpart, &serverName,
 		&openIDTokenAttrs.ExpiresAtMS,
 	)
+	openIDTokenAttrs.UserID = fmt.Sprintf("@%s:%s", localpart, serverName)
 	if err != nil {
 		if err != sql.ErrNoRows {
 			log.WithError(err).Error("Unable to retrieve token from the db")
diff --git a/userapi/storage/sqlite3/profile_table.go b/userapi/storage/sqlite3/profile_table.go
index b6130a1e..867026d7 100644
--- a/userapi/storage/sqlite3/profile_table.go
+++ b/userapi/storage/sqlite3/profile_table.go
@@ -23,36 +23,40 @@ import (
 	"github.com/matrix-org/dendrite/internal"
 	"github.com/matrix-org/dendrite/internal/sqlutil"
 	"github.com/matrix-org/dendrite/userapi/storage/tables"
+	"github.com/matrix-org/gomatrixserverlib"
 )
 
 const profilesSchema = `
 -- Stores data about accounts profiles.
 CREATE TABLE IF NOT EXISTS userapi_profiles (
     -- The Matrix user ID localpart for this account
-    localpart TEXT NOT NULL PRIMARY KEY,
+    localpart TEXT NOT NULL,
+	server_name TEXT NOT NULL,
     -- The display name for this account
     display_name TEXT,
     -- The URL of the avatar for this account
     avatar_url TEXT
 );
+
+CREATE UNIQUE INDEX IF NOT EXISTS userapi_profiles_idx ON userapi_profiles(localpart, server_name);
 `
 
 const insertProfileSQL = "" +
-	"INSERT INTO userapi_profiles(localpart, display_name, avatar_url) VALUES ($1, $2, $3)"
+	"INSERT INTO userapi_profiles(localpart, server_name, display_name, avatar_url) VALUES ($1, $2, $3, $4)"
 
 const selectProfileByLocalpartSQL = "" +
-	"SELECT localpart, display_name, avatar_url FROM userapi_profiles WHERE localpart = $1"
+	"SELECT localpart, server_name, display_name, avatar_url FROM userapi_profiles WHERE localpart = $1 AND server_name = $2"
 
 const setAvatarURLSQL = "" +
-	"UPDATE userapi_profiles SET avatar_url = $1 WHERE localpart = $2" +
+	"UPDATE userapi_profiles SET avatar_url = $1 WHERE localpart = $2 AND server_name = $3" +
 	" RETURNING display_name"
 
 const setDisplayNameSQL = "" +
-	"UPDATE userapi_profiles SET display_name = $1 WHERE localpart = $2" +
+	"UPDATE userapi_profiles SET display_name = $1 WHERE localpart = $2 AND server_name = $3" +
 	" RETURNING avatar_url"
 
 const selectProfilesBySearchSQL = "" +
-	"SELECT localpart, display_name, avatar_url FROM userapi_profiles WHERE localpart LIKE $1 OR display_name LIKE $1 LIMIT $2"
+	"SELECT localpart, server_name, display_name, avatar_url FROM userapi_profiles WHERE localpart LIKE $1 OR display_name LIKE $1 LIMIT $2"
 
 type profilesStatements struct {
 	db                           *sql.DB
@@ -83,18 +87,20 @@ func NewSQLiteProfilesTable(db *sql.DB, serverNoticesLocalpart string) (tables.P
 }
 
 func (s *profilesStatements) InsertProfile(
-	ctx context.Context, txn *sql.Tx, localpart string,
+	ctx context.Context, txn *sql.Tx,
+	localpart string, serverName gomatrixserverlib.ServerName,
 ) error {
-	_, err := sqlutil.TxStmt(txn, s.insertProfileStmt).ExecContext(ctx, localpart, "", "")
+	_, err := sqlutil.TxStmt(txn, s.insertProfileStmt).ExecContext(ctx, localpart, serverName, "", "")
 	return err
 }
 
 func (s *profilesStatements) SelectProfileByLocalpart(
-	ctx context.Context, localpart string,
+	ctx context.Context,
+	localpart string, serverName gomatrixserverlib.ServerName,
 ) (*authtypes.Profile, error) {
 	var profile authtypes.Profile
-	err := s.selectProfileByLocalpartStmt.QueryRowContext(ctx, localpart).Scan(
-		&profile.Localpart, &profile.DisplayName, &profile.AvatarURL,
+	err := s.selectProfileByLocalpartStmt.QueryRowContext(ctx, localpart, serverName).Scan(
+		&profile.Localpart, &profile.ServerName, &profile.DisplayName, &profile.AvatarURL,
 	)
 	if err != nil {
 		return nil, err
@@ -103,13 +109,16 @@ func (s *profilesStatements) SelectProfileByLocalpart(
 }
 
 func (s *profilesStatements) SetAvatarURL(
-	ctx context.Context, txn *sql.Tx, localpart string, avatarURL string,
+	ctx context.Context, txn *sql.Tx,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	avatarURL string,
 ) (*authtypes.Profile, bool, error) {
 	profile := &authtypes.Profile{
-		Localpart: localpart,
-		AvatarURL: avatarURL,
+		Localpart:  localpart,
+		ServerName: string(serverName),
+		AvatarURL:  avatarURL,
 	}
-	old, err := s.SelectProfileByLocalpart(ctx, localpart)
+	old, err := s.SelectProfileByLocalpart(ctx, localpart, serverName)
 	if err != nil {
 		return old, false, err
 	}
@@ -117,18 +126,21 @@ func (s *profilesStatements) SetAvatarURL(
 		return old, false, nil
 	}
 	stmt := sqlutil.TxStmt(txn, s.setAvatarURLStmt)
-	err = stmt.QueryRowContext(ctx, avatarURL, localpart).Scan(&profile.DisplayName)
+	err = stmt.QueryRowContext(ctx, avatarURL, localpart, serverName).Scan(&profile.DisplayName)
 	return profile, true, err
 }
 
 func (s *profilesStatements) SetDisplayName(
-	ctx context.Context, txn *sql.Tx, localpart string, displayName string,
+	ctx context.Context, txn *sql.Tx,
+	localpart string, serverName gomatrixserverlib.ServerName,
+	displayName string,
 ) (*authtypes.Profile, bool, error) {
 	profile := &authtypes.Profile{
 		Localpart:   localpart,
+		ServerName:  string(serverName),
 		DisplayName: displayName,
 	}
-	old, err := s.SelectProfileByLocalpart(ctx, localpart)
+	old, err := s.SelectProfileByLocalpart(ctx, localpart, serverName)
 	if err != nil {
 		return old, false, err
 	}
@@ -136,7 +148,7 @@ func (s *profilesStatements) SetDisplayName(
 		return old, false, nil
 	}
 	stmt := sqlutil.TxStmt(txn, s.setDisplayNameStmt)
-	err = stmt.QueryRowContext(ctx, displayName, localpart).Scan(&profile.AvatarURL)
+	err = stmt.QueryRowContext(ctx, displayName, localpart, serverName).Scan(&profile.AvatarURL)
 	return profile, true, err
 }
 
@@ -154,7 +166,7 @@ func (s *profilesStatements) SelectProfilesBySearch(
 	defer internal.CloseAndLogIfError(ctx, rows, "selectProfilesBySearch: rows.close() failed")
 	for rows.Next() {
 		var profile authtypes.Profile
-		if err := rows.Scan(&profile.Localpart, &profile.DisplayName, &profile.AvatarURL); err != nil {
+		if err := rows.Scan(&profile.Localpart, &profile.ServerName, &profile.DisplayName, &profile.AvatarURL); err != nil {
 			return nil, err
 		}
 		if profile.Localpart != s.serverNoticesLocalpart {
diff --git a/userapi/storage/sqlite3/pusher_table.go b/userapi/storage/sqlite3/pusher_table.go
index 4de0a9f0..c9d451dc 100644
--- a/userapi/storage/sqlite3/pusher_table.go
+++ b/userapi/storage/sqlite3/pusher_table.go
@@ -25,6 +25,7 @@ import (
 	"github.com/matrix-org/dendrite/internal/sqlutil"
 	"github.com/matrix-org/dendrite/userapi/api"
 	"github.com/matrix-org/dendrite/userapi/storage/tables"
+	"github.com/matrix-org/gomatrixserverlib"
 )
 
 // See https://matrix.org/docs/spec/client_server/r0.6.1#get-matrix-client-r0-pushers
@@ -33,6 +34,7 @@ CREATE TABLE IF NOT EXISTS userapi_pushers (
 	id INTEGER PRIMARY KEY AUTOINCREMENT,
 	-- The Matrix user ID localpart for this pusher
 	localpart TEXT NOT NULL,
+	server_name TEXT NOT NULL,
 	session_id BIGINT DEFAULT NULL,
 	profile_tag TEXT,
 	kind TEXT NOT NULL,
@@ -49,22 +51,22 @@ CREATE TABLE IF NOT EXISTS userapi_pushers (
 CREATE INDEX IF NOT EXISTS userapi_pusher_app_id_pushkey_idx ON userapi_pushers(app_id, pushkey);
 
 -- For faster retrieving by localpart.
-CREATE INDEX IF NOT EXISTS userapi_pusher_localpart_idx ON userapi_pushers(localpart);
+CREATE INDEX IF NOT EXISTS userapi_pusher_localpart_idx ON userapi_pushers(localpart, server_name);
 
 -- Pushkey must be unique for a given user and app.
-CREATE UNIQUE INDEX IF NOT EXISTS userapi_pusher_app_id_pushkey_localpart_idx ON userapi_pushers(app_id, pushkey, localpart);
+CREATE UNIQUE INDEX IF NOT EXISTS userapi_pusher_app_id_pushkey_localpart_idx ON userapi_pushers(app_id, pushkey, localpart, server_name);
 `
 
 const insertPusherSQL = "" +
-	"INSERT INTO userapi_pushers (localpart, session_id, pushkey, pushkey_ts_ms, kind, app_id, app_display_name, device_display_name, profile_tag, lang, data)" +
-	"VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11)" +
-	"ON CONFLICT (app_id, pushkey, localpart) DO UPDATE SET session_id = $2, pushkey_ts_ms = $4, kind = $5, app_display_name = $7, device_display_name = $8, profile_tag = $9, lang = $10, data = $11"
+	"INSERT INTO userapi_pushers (localpart, server_name, session_id, pushkey, pushkey_ts_ms, kind, app_id, app_display_name, device_display_name, profile_tag, lang, data)" +
+	"VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11, $12)" +
+	"ON CONFLICT (app_id, pushkey, localpart, server_name) DO UPDATE SET session_id = $3, pushkey_ts_ms = $5, kind = $6, app_display_name = $8, device_display_name = $9, profile_tag = $10, lang = $11, data = $12"
 
 const selectPushersSQL = "" +
-	"SELECT session_id, pushkey, pushkey_ts_ms, kind, app_id, app_display_name, device_display_name, profile_tag, lang, data FROM userapi_pushers WHERE localpart = $1"
+	"SELECT session_id, pushkey, pushkey_ts_ms, kind, app_id, app_display_name, device_display_name, profile_tag, lang, data FROM userapi_pushers WHERE localpart = $1 AND server_name = $2"
 
 const deletePusherSQL = "" +
-	"DELETE FROM userapi_pushers WHERE app_id = $1 AND pushkey = $2 AND localpart = $3"
+	"DELETE FROM userapi_pushers WHERE app_id = $1 AND pushkey = $2 AND localpart = $3 AND server_name = $4"
 
 const deletePushersByAppIdAndPushKeySQL = "" +
 	"DELETE FROM userapi_pushers WHERE app_id = $1 AND pushkey = $2"
@@ -95,18 +97,19 @@ type pushersStatements struct {
 // Returns nil error success.
 func (s *pushersStatements) InsertPusher(
 	ctx context.Context, txn *sql.Tx, session_id int64,
-	pushkey string, pushkeyTS int64, kind api.PusherKind, appid, appdisplayname, devicedisplayname, profiletag, lang, data, localpart string,
+	pushkey string, pushkeyTS int64, kind api.PusherKind, appid, appdisplayname, devicedisplayname, profiletag, lang, data,
+	localpart string, serverName gomatrixserverlib.ServerName,
 ) error {
-	_, err := sqlutil.TxStmt(txn, s.insertPusherStmt).ExecContext(ctx, localpart, session_id, pushkey, pushkeyTS, kind, appid, appdisplayname, devicedisplayname, profiletag, lang, data)
-	logrus.Debugf("Created pusher %d", session_id)
+	_, err := sqlutil.TxStmt(txn, s.insertPusherStmt).ExecContext(ctx, localpart, serverName, session_id, pushkey, pushkeyTS, kind, appid, appdisplayname, devicedisplayname, profiletag, lang, data)
 	return err
 }
 
 func (s *pushersStatements) SelectPushers(
-	ctx context.Context, txn *sql.Tx, localpart string,
+	ctx context.Context, txn *sql.Tx,
+	localpart string, serverName gomatrixserverlib.ServerName,
 ) ([]api.Pusher, error) {
 	pushers := []api.Pusher{}
-	rows, err := s.selectPushersStmt.QueryContext(ctx, localpart)
+	rows, err := s.selectPushersStmt.QueryContext(ctx, localpart, serverName)
 
 	if err != nil {
 		return pushers, err
@@ -143,9 +146,10 @@ func (s *pushersStatements) SelectPushers(
 
 // deletePusher removes a single pusher by pushkey and user localpart.
 func (s *pushersStatements) DeletePusher(
-	ctx context.Context, txn *sql.Tx, appid, pushkey, localpart string,
+	ctx context.Context, txn *sql.Tx, appid, pushkey,
+	localpart string, serverName gomatrixserverlib.ServerName,
 ) error {
-	_, err := sqlutil.TxStmt(txn, s.deletePusherStmt).ExecContext(ctx, appid, pushkey, localpart)
+	_, err := sqlutil.TxStmt(txn, s.deletePusherStmt).ExecContext(ctx, appid, pushkey, localpart, serverName)
 	return err
 }
 
diff --git a/userapi/storage/sqlite3/storage.go b/userapi/storage/sqlite3/storage.go
index dd33dc0c..85a1f706 100644
--- a/userapi/storage/sqlite3/storage.go
+++ b/userapi/storage/sqlite3/storage.go
@@ -15,6 +15,8 @@
 package sqlite3
 
 import (
+	"context"
+	"database/sql"
 	"fmt"
 	"time"
 
@@ -41,18 +43,24 @@ func NewDatabase(base *base.BaseDendrite, dbProperties *config.DatabaseOptions,
 		Up:      deltas.UpRenameTables,
 		Down:    deltas.DownRenameTables,
 	})
+	m.AddMigrations(sqlutil.Migration{
+		Version: "userapi: server names",
+		Up: func(ctx context.Context, txn *sql.Tx) error {
+			return deltas.UpServerNames(ctx, txn, serverName)
+		},
+	})
 	if err = m.Up(base.Context()); err != nil {
 		return nil, err
 	}
 
-	accountDataTable, err := NewSQLiteAccountDataTable(db)
-	if err != nil {
-		return nil, fmt.Errorf("NewSQLiteAccountDataTable: %w", err)
-	}
 	accountsTable, err := NewSQLiteAccountsTable(db, serverName)
 	if err != nil {
 		return nil, fmt.Errorf("NewSQLiteAccountsTable: %w", err)
 	}
+	accountDataTable, err := NewSQLiteAccountDataTable(db)
+	if err != nil {
+		return nil, fmt.Errorf("NewSQLiteAccountDataTable: %w", err)
+	}
 	devicesTable, err := NewSQLiteDevicesTable(db, serverName)
 	if err != nil {
 		return nil, fmt.Errorf("NewSQLiteDevicesTable: %w", err)
@@ -93,6 +101,18 @@ func NewDatabase(base *base.BaseDendrite, dbProperties *config.DatabaseOptions,
 	if err != nil {
 		return nil, fmt.Errorf("NewSQLiteStatsTable: %w", err)
 	}
+
+	m = sqlutil.NewMigrator(db)
+	m.AddMigrations(sqlutil.Migration{
+		Version: "userapi: server names populate",
+		Up: func(ctx context.Context, txn *sql.Tx) error {
+			return deltas.UpServerNamesPopulate(ctx, txn, serverName)
+		},
+	})
+	if err = m.Up(base.Context()); err != nil {
+		return nil, err
+	}
+
 	return &shared.Database{
 		AccountDatas:          accountDataTable,
 		Accounts:              accountsTable,
diff --git a/userapi/storage/sqlite3/threepid_table.go b/userapi/storage/sqlite3/threepid_table.go
index 73af139d..2db7d588 100644
--- a/userapi/storage/sqlite3/threepid_table.go
+++ b/userapi/storage/sqlite3/threepid_table.go
@@ -21,6 +21,7 @@ import (
 	"github.com/matrix-org/dendrite/internal"
 	"github.com/matrix-org/dendrite/internal/sqlutil"
 	"github.com/matrix-org/dendrite/userapi/storage/tables"
+	"github.com/matrix-org/gomatrixserverlib"
 
 	"github.com/matrix-org/dendrite/clientapi/auth/authtypes"
 )
@@ -34,21 +35,22 @@ CREATE TABLE IF NOT EXISTS userapi_threepids (
 	medium TEXT NOT NULL DEFAULT 'email',
 	-- The localpart of the Matrix user ID associated to this 3PID
 	localpart TEXT NOT NULL,
+	server_name TEXT NOT NULL,
 
 	PRIMARY KEY(threepid, medium)
 );
 
-CREATE INDEX IF NOT EXISTS account_threepid_localpart ON userapi_threepids(localpart);
+CREATE INDEX IF NOT EXISTS account_threepid_localpart ON userapi_threepids(localpart, server_name);
 `
 
 const selectLocalpartForThreePIDSQL = "" +
-	"SELECT localpart FROM userapi_threepids WHERE threepid = $1 AND medium = $2"
+	"SELECT localpart, server_name FROM userapi_threepids WHERE threepid = $1 AND medium = $2"
 
 const selectThreePIDsForLocalpartSQL = "" +
-	"SELECT threepid, medium FROM userapi_threepids WHERE localpart = $1"
+	"SELECT threepid, medium FROM userapi_threepids WHERE localpart = $1 AND server_name = $2"
 
 const insertThreePIDSQL = "" +
-	"INSERT INTO userapi_threepids (threepid, medium, localpart) VALUES ($1, $2, $3)"
+	"INSERT INTO userapi_threepids (threepid, medium, localpart, server_name) VALUES ($1, $2, $3, $4)"
 
 const deleteThreePIDSQL = "" +
 	"DELETE FROM userapi_threepids WHERE threepid = $1 AND medium = $2"
@@ -79,19 +81,20 @@ func NewSQLiteThreePIDTable(db *sql.DB) (tables.ThreePIDTable, error) {
 
 func (s *threepidStatements) SelectLocalpartForThreePID(
 	ctx context.Context, txn *sql.Tx, threepid string, medium string,
-) (localpart string, err error) {
+) (localpart string, serverName gomatrixserverlib.ServerName, err error) {
 	stmt := sqlutil.TxStmt(txn, s.selectLocalpartForThreePIDStmt)
-	err = stmt.QueryRowContext(ctx, threepid, medium).Scan(&localpart)
+	err = stmt.QueryRowContext(ctx, threepid, medium).Scan(&localpart, &serverName)
 	if err == sql.ErrNoRows {
-		return "", nil
+		return "", "", nil
 	}
 	return
 }
 
 func (s *threepidStatements) SelectThreePIDsForLocalpart(
-	ctx context.Context, localpart string,
+	ctx context.Context,
+	localpart string, serverName gomatrixserverlib.ServerName,
 ) (threepids []authtypes.ThreePID, err error) {
-	rows, err := s.selectThreePIDsForLocalpartStmt.QueryContext(ctx, localpart)
+	rows, err := s.selectThreePIDsForLocalpartStmt.QueryContext(ctx, localpart, serverName)
 	if err != nil {
 		return
 	}
@@ -113,10 +116,11 @@ func (s *threepidStatements) SelectThreePIDsForLocalpart(
 }
 
 func (s *threepidStatements) InsertThreePID(
-	ctx context.Context, txn *sql.Tx, threepid, medium, localpart string,
+	ctx context.Context, txn *sql.Tx, threepid, medium,
+	localpart string, serverName gomatrixserverlib.ServerName,
 ) (err error) {
 	stmt := sqlutil.TxStmt(txn, s.insertThreePIDStmt)
-	_, err = stmt.ExecContext(ctx, threepid, medium, localpart)
+	_, err = stmt.ExecContext(ctx, threepid, medium, localpart, serverName)
 	return err
 }
 
diff --git a/userapi/storage/storage_test.go b/userapi/storage/storage_test.go
index 354f085f..23aafff0 100644
--- a/userapi/storage/storage_test.go
+++ b/userapi/storage/storage_test.go
@@ -50,25 +50,25 @@ func Test_AccountData(t *testing.T) {
 		db, close := mustCreateDatabase(t, dbType)
 		defer close()
 		alice := test.NewUser(t)
-		localpart, _, err := gomatrixserverlib.SplitID('@', alice.ID)
+		localpart, domain, err := gomatrixserverlib.SplitID('@', alice.ID)
 		assert.NoError(t, err)
 
 		room := test.NewRoom(t, alice)
 		events := room.Events()
 
 		contentRoom := json.RawMessage(fmt.Sprintf(`{"event_id":"%s"}`, events[len(events)-1].EventID()))
-		err = db.SaveAccountData(ctx, localpart, room.ID, "m.fully_read", contentRoom)
+		err = db.SaveAccountData(ctx, localpart, domain, room.ID, "m.fully_read", contentRoom)
 		assert.NoError(t, err, "unable to save account data")
 
 		contentGlobal := json.RawMessage(fmt.Sprintf(`{"recent_rooms":["%s"]}`, room.ID))
-		err = db.SaveAccountData(ctx, localpart, "", "im.vector.setting.breadcrumbs", contentGlobal)
+		err = db.SaveAccountData(ctx, localpart, domain, "", "im.vector.setting.breadcrumbs", contentGlobal)
 		assert.NoError(t, err, "unable to save account data")
 
-		accountData, err := db.GetAccountDataByType(ctx, localpart, room.ID, "m.fully_read")
+		accountData, err := db.GetAccountDataByType(ctx, localpart, domain, room.ID, "m.fully_read")
 		assert.NoError(t, err, "unable to get account data by type")
 		assert.Equal(t, contentRoom, accountData)
 
-		globalData, roomData, err := db.GetAccountData(ctx, localpart)
+		globalData, roomData, err := db.GetAccountData(ctx, localpart, domain)
 		assert.NoError(t, err)
 		assert.Equal(t, contentRoom, roomData[room.ID]["m.fully_read"])
 		assert.Equal(t, contentGlobal, globalData["im.vector.setting.breadcrumbs"])
@@ -81,78 +81,78 @@ func Test_Accounts(t *testing.T) {
 		db, close := mustCreateDatabase(t, dbType)
 		defer close()
 		alice := test.NewUser(t)
-		aliceLocalpart, _, err := gomatrixserverlib.SplitID('@', alice.ID)
+		aliceLocalpart, aliceDomain, err := gomatrixserverlib.SplitID('@', alice.ID)
 		assert.NoError(t, err)
 
-		accAlice, err := db.CreateAccount(ctx, aliceLocalpart, "testing", "", api.AccountTypeAdmin)
+		accAlice, err := db.CreateAccount(ctx, aliceLocalpart, aliceDomain, "testing", "", api.AccountTypeAdmin)
 		assert.NoError(t, err, "failed to create account")
 		// verify the newly create account is the same as returned by CreateAccount
 		var accGet *api.Account
-		accGet, err = db.GetAccountByPassword(ctx, aliceLocalpart, "testing")
+		accGet, err = db.GetAccountByPassword(ctx, aliceLocalpart, aliceDomain, "testing")
 		assert.NoError(t, err, "failed to get account by password")
 		assert.Equal(t, accAlice, accGet)
-		accGet, err = db.GetAccountByLocalpart(ctx, aliceLocalpart)
+		accGet, err = db.GetAccountByLocalpart(ctx, aliceLocalpart, aliceDomain)
 		assert.NoError(t, err, "failed to get account by localpart")
 		assert.Equal(t, accAlice, accGet)
 
 		// check account availability
-		available, err := db.CheckAccountAvailability(ctx, aliceLocalpart)
+		available, err := db.CheckAccountAvailability(ctx, aliceLocalpart, aliceDomain)
 		assert.NoError(t, err, "failed to checkout account availability")
 		assert.Equal(t, false, available)
 
-		available, err = db.CheckAccountAvailability(ctx, "unusedname")
+		available, err = db.CheckAccountAvailability(ctx, "unusedname", aliceDomain)
 		assert.NoError(t, err, "failed to checkout account availability")
 		assert.Equal(t, true, available)
 
 		// get guest account numeric aliceLocalpart
-		first, err := db.GetNewNumericLocalpart(ctx)
+		first, err := db.GetNewNumericLocalpart(ctx, aliceDomain)
 		assert.NoError(t, err, "failed to get new numeric localpart")
 		// Create a new account to verify the numeric localpart is updated
-		_, err = db.CreateAccount(ctx, "", "testing", "", api.AccountTypeGuest)
+		_, err = db.CreateAccount(ctx, "", aliceDomain, "testing", "", api.AccountTypeGuest)
 		assert.NoError(t, err, "failed to create account")
-		second, err := db.GetNewNumericLocalpart(ctx)
+		second, err := db.GetNewNumericLocalpart(ctx, aliceDomain)
 		assert.NoError(t, err)
 		assert.Greater(t, second, first)
 
 		// update password for alice
-		err = db.SetPassword(ctx, aliceLocalpart, "newPassword")
+		err = db.SetPassword(ctx, aliceLocalpart, aliceDomain, "newPassword")
 		assert.NoError(t, err, "failed to update password")
-		accGet, err = db.GetAccountByPassword(ctx, aliceLocalpart, "newPassword")
+		accGet, err = db.GetAccountByPassword(ctx, aliceLocalpart, aliceDomain, "newPassword")
 		assert.NoError(t, err, "failed to get account by new password")
 		assert.Equal(t, accAlice, accGet)
 
 		// deactivate account
-		err = db.DeactivateAccount(ctx, aliceLocalpart)
+		err = db.DeactivateAccount(ctx, aliceLocalpart, aliceDomain)
 		assert.NoError(t, err, "failed to deactivate account")
 		// This should fail now, as the account is deactivated
-		_, err = db.GetAccountByPassword(ctx, aliceLocalpart, "newPassword")
+		_, err = db.GetAccountByPassword(ctx, aliceLocalpart, aliceDomain, "newPassword")
 		assert.Error(t, err, "expected an error, got none")
 
-		_, err = db.GetAccountByLocalpart(ctx, "unusename")
+		_, err = db.GetAccountByLocalpart(ctx, "unusename", aliceDomain)
 		assert.Error(t, err, "expected an error for non existent localpart")
 
 		// create an empty localpart; this should never happen, but is required to test getting a numeric localpart
 		// if there's already a user without a localpart in the database
-		_, err = db.CreateAccount(ctx, "", "", "", api.AccountTypeUser)
+		_, err = db.CreateAccount(ctx, "", aliceDomain, "", "", api.AccountTypeUser)
 		assert.NoError(t, err)
 
 		// test getting a numeric localpart, with an existing user without a localpart
-		_, err = db.CreateAccount(ctx, "", "", "", api.AccountTypeGuest)
+		_, err = db.CreateAccount(ctx, "", aliceDomain, "", "", api.AccountTypeGuest)
 		assert.NoError(t, err)
 
 		// Create a user with a high numeric localpart, out of range for the Postgres integer (2147483647) type
-		_, err = db.CreateAccount(ctx, "2147483650", "", "", api.AccountTypeUser)
+		_, err = db.CreateAccount(ctx, "2147483650", aliceDomain, "", "", api.AccountTypeUser)
 		assert.NoError(t, err)
 
 		// Now try to create a new guest user
-		_, err = db.CreateAccount(ctx, "", "", "", api.AccountTypeGuest)
+		_, err = db.CreateAccount(ctx, "", aliceDomain, "", "", api.AccountTypeGuest)
 		assert.NoError(t, err)
 	})
 }
 
 func Test_Devices(t *testing.T) {
 	alice := test.NewUser(t)
-	localpart, _, err := gomatrixserverlib.SplitID('@', alice.ID)
+	localpart, domain, err := gomatrixserverlib.SplitID('@', alice.ID)
 	assert.NoError(t, err)
 	deviceID := util.RandomString(8)
 	accessToken := util.RandomString(16)
@@ -161,10 +161,10 @@ func Test_Devices(t *testing.T) {
 		db, close := mustCreateDatabase(t, dbType)
 		defer close()
 
-		deviceWithID, err := db.CreateDevice(ctx, localpart, &deviceID, accessToken, nil, "", "")
+		deviceWithID, err := db.CreateDevice(ctx, localpart, domain, &deviceID, accessToken, nil, "", "")
 		assert.NoError(t, err, "unable to create deviceWithoutID")
 
-		gotDevice, err := db.GetDeviceByID(ctx, localpart, deviceID)
+		gotDevice, err := db.GetDeviceByID(ctx, localpart, domain, deviceID)
 		assert.NoError(t, err, "unable to get device by id")
 		assert.Equal(t, deviceWithID.ID, gotDevice.ID) // GetDeviceByID doesn't populate all fields
 
@@ -174,14 +174,14 @@ func Test_Devices(t *testing.T) {
 
 		// create a device without existing device ID
 		accessToken = util.RandomString(16)
-		deviceWithoutID, err := db.CreateDevice(ctx, localpart, nil, accessToken, nil, "", "")
+		deviceWithoutID, err := db.CreateDevice(ctx, localpart, domain, nil, accessToken, nil, "", "")
 		assert.NoError(t, err, "unable to create deviceWithoutID")
-		gotDeviceWithoutID, err := db.GetDeviceByID(ctx, localpart, deviceWithoutID.ID)
+		gotDeviceWithoutID, err := db.GetDeviceByID(ctx, localpart, domain, deviceWithoutID.ID)
 		assert.NoError(t, err, "unable to get device by id")
 		assert.Equal(t, deviceWithoutID.ID, gotDeviceWithoutID.ID) // GetDeviceByID doesn't populate all fields
 
 		// Get devices
-		devices, err := db.GetDevicesByLocalpart(ctx, localpart)
+		devices, err := db.GetDevicesByLocalpart(ctx, localpart, domain)
 		assert.NoError(t, err, "unable to get devices by localpart")
 		assert.Equal(t, 2, len(devices))
 		deviceIDs := make([]string, 0, len(devices))
@@ -195,15 +195,15 @@ func Test_Devices(t *testing.T) {
 
 		// Update device
 		newName := "new display name"
-		err = db.UpdateDevice(ctx, localpart, deviceWithID.ID, &newName)
+		err = db.UpdateDevice(ctx, localpart, domain, deviceWithID.ID, &newName)
 		assert.NoError(t, err, "unable to update device displayname")
 		updatedAfterTimestamp := time.Now().Unix()
-		err = db.UpdateDeviceLastSeen(ctx, localpart, deviceWithID.ID, "127.0.0.1", "Element Web")
+		err = db.UpdateDeviceLastSeen(ctx, localpart, domain, deviceWithID.ID, "127.0.0.1", "Element Web")
 		assert.NoError(t, err, "unable to update device last seen")
 
 		deviceWithID.DisplayName = newName
 		deviceWithID.LastSeenIP = "127.0.0.1"
-		gotDevice, err = db.GetDeviceByID(ctx, localpart, deviceWithID.ID)
+		gotDevice, err = db.GetDeviceByID(ctx, localpart, domain, deviceWithID.ID)
 		assert.NoError(t, err, "unable to get device by id")
 		assert.Equal(t, 2, len(devices))
 		assert.Equal(t, deviceWithID.DisplayName, gotDevice.DisplayName)
@@ -213,20 +213,20 @@ func Test_Devices(t *testing.T) {
 		// create one more device and remove the devices step by step
 		newDeviceID := util.RandomString(16)
 		accessToken = util.RandomString(16)
-		_, err = db.CreateDevice(ctx, localpart, &newDeviceID, accessToken, nil, "", "")
+		_, err = db.CreateDevice(ctx, localpart, domain, &newDeviceID, accessToken, nil, "", "")
 		assert.NoError(t, err, "unable to create new device")
 
-		devices, err = db.GetDevicesByLocalpart(ctx, localpart)
+		devices, err = db.GetDevicesByLocalpart(ctx, localpart, domain)
 		assert.NoError(t, err, "unable to get device by id")
 		assert.Equal(t, 3, len(devices))
 
-		err = db.RemoveDevices(ctx, localpart, deviceIDs)
+		err = db.RemoveDevices(ctx, localpart, domain, deviceIDs)
 		assert.NoError(t, err, "unable to remove devices")
-		devices, err = db.GetDevicesByLocalpart(ctx, localpart)
+		devices, err = db.GetDevicesByLocalpart(ctx, localpart, domain)
 		assert.NoError(t, err, "unable to get device by id")
 		assert.Equal(t, 1, len(devices))
 
-		deleted, err := db.RemoveAllDevices(ctx, localpart, "")
+		deleted, err := db.RemoveAllDevices(ctx, localpart, domain, "")
 		assert.NoError(t, err, "unable to remove all devices")
 		assert.Equal(t, 1, len(deleted))
 		assert.Equal(t, newDeviceID, deleted[0].ID)
@@ -364,7 +364,7 @@ func Test_OpenID(t *testing.T) {
 
 func Test_Profile(t *testing.T) {
 	alice := test.NewUser(t)
-	aliceLocalpart, _, err := gomatrixserverlib.SplitID('@', alice.ID)
+	aliceLocalpart, aliceDomain, err := gomatrixserverlib.SplitID('@', alice.ID)
 	assert.NoError(t, err)
 
 	test.WithAllDatabases(t, func(t *testing.T, dbType test.DBType) {
@@ -372,30 +372,33 @@ func Test_Profile(t *testing.T) {
 		defer close()
 
 		// create account, which also creates a profile
-		_, err = db.CreateAccount(ctx, aliceLocalpart, "testing", "", api.AccountTypeAdmin)
+		_, err = db.CreateAccount(ctx, aliceLocalpart, aliceDomain, "testing", "", api.AccountTypeAdmin)
 		assert.NoError(t, err, "failed to create account")
 
-		gotProfile, err := db.GetProfileByLocalpart(ctx, aliceLocalpart)
+		gotProfile, err := db.GetProfileByLocalpart(ctx, aliceLocalpart, aliceDomain)
 		assert.NoError(t, err, "unable to get profile by localpart")
-		wantProfile := &authtypes.Profile{Localpart: aliceLocalpart}
+		wantProfile := &authtypes.Profile{
+			Localpart:  aliceLocalpart,
+			ServerName: string(aliceDomain),
+		}
 		assert.Equal(t, wantProfile, gotProfile)
 
 		// set avatar & displayname
 		wantProfile.DisplayName = "Alice"
-		gotProfile, changed, err := db.SetDisplayName(ctx, aliceLocalpart, "Alice")
+		gotProfile, changed, err := db.SetDisplayName(ctx, aliceLocalpart, aliceDomain, "Alice")
 		assert.Equal(t, wantProfile, gotProfile)
 		assert.NoError(t, err, "unable to set displayname")
 		assert.True(t, changed)
 
 		wantProfile.AvatarURL = "mxc://aliceAvatar"
-		gotProfile, changed, err = db.SetAvatarURL(ctx, aliceLocalpart, "mxc://aliceAvatar")
+		gotProfile, changed, err = db.SetAvatarURL(ctx, aliceLocalpart, aliceDomain, "mxc://aliceAvatar")
 		assert.NoError(t, err, "unable to set avatar url")
 		assert.Equal(t, wantProfile, gotProfile)
 		assert.True(t, changed)
 
 		// Setting the same avatar again doesn't change anything
 		wantProfile.AvatarURL = "mxc://aliceAvatar"
-		gotProfile, changed, err = db.SetAvatarURL(ctx, aliceLocalpart, "mxc://aliceAvatar")
+		gotProfile, changed, err = db.SetAvatarURL(ctx, aliceLocalpart, aliceDomain, "mxc://aliceAvatar")
 		assert.NoError(t, err, "unable to set avatar url")
 		assert.Equal(t, wantProfile, gotProfile)
 		assert.False(t, changed)
@@ -410,7 +413,7 @@ func Test_Profile(t *testing.T) {
 
 func Test_Pusher(t *testing.T) {
 	alice := test.NewUser(t)
-	aliceLocalpart, _, err := gomatrixserverlib.SplitID('@', alice.ID)
+	aliceLocalpart, aliceDomain, err := gomatrixserverlib.SplitID('@', alice.ID)
 	assert.NoError(t, err)
 
 	test.WithAllDatabases(t, func(t *testing.T, dbType test.DBType) {
@@ -432,11 +435,11 @@ func Test_Pusher(t *testing.T) {
 				ProfileTag:        util.RandomString(8),
 				Language:          util.RandomString(2),
 			}
-			err = db.UpsertPusher(ctx, wantPusher, aliceLocalpart)
+			err = db.UpsertPusher(ctx, wantPusher, aliceLocalpart, aliceDomain)
 			assert.NoError(t, err, "unable to upsert pusher")
 
 			// check it was actually persisted
-			gotPushers, err = db.GetPushers(ctx, aliceLocalpart)
+			gotPushers, err = db.GetPushers(ctx, aliceLocalpart, aliceDomain)
 			assert.NoError(t, err, "unable to get pushers")
 			assert.Equal(t, i+1, len(gotPushers))
 			assert.Equal(t, wantPusher, gotPushers[i])
@@ -444,16 +447,16 @@ func Test_Pusher(t *testing.T) {
 		}
 
 		// remove single pusher
-		err = db.RemovePusher(ctx, appID, pushKeys[0], aliceLocalpart)
+		err = db.RemovePusher(ctx, appID, pushKeys[0], aliceLocalpart, aliceDomain)
 		assert.NoError(t, err, "unable to remove pusher")
-		gotPushers, err := db.GetPushers(ctx, aliceLocalpart)
+		gotPushers, err := db.GetPushers(ctx, aliceLocalpart, aliceDomain)
 		assert.NoError(t, err, "unable to get pushers")
 		assert.Equal(t, 1, len(gotPushers))
 
 		// remove last pusher
 		err = db.RemovePushers(ctx, appID, pushKeys[1])
 		assert.NoError(t, err, "unable to remove pusher")
-		gotPushers, err = db.GetPushers(ctx, aliceLocalpart)
+		gotPushers, err = db.GetPushers(ctx, aliceLocalpart, aliceDomain)
 		assert.NoError(t, err, "unable to get pushers")
 		assert.Equal(t, 0, len(gotPushers))
 	})
@@ -461,7 +464,7 @@ func Test_Pusher(t *testing.T) {
 
 func Test_ThreePID(t *testing.T) {
 	alice := test.NewUser(t)
-	aliceLocalpart, _, err := gomatrixserverlib.SplitID('@', alice.ID)
+	aliceLocalpart, aliceDomain, err := gomatrixserverlib.SplitID('@', alice.ID)
 	assert.NoError(t, err)
 
 	test.WithAllDatabases(t, func(t *testing.T, dbType test.DBType) {
@@ -469,15 +472,16 @@ func Test_ThreePID(t *testing.T) {
 		defer close()
 		threePID := util.RandomString(8)
 		medium := util.RandomString(8)
-		err = db.SaveThreePIDAssociation(ctx, threePID, aliceLocalpart, medium)
+		err = db.SaveThreePIDAssociation(ctx, threePID, aliceLocalpart, aliceDomain, medium)
 		assert.NoError(t, err, "unable to save threepid association")
 
 		// get the stored threepid
-		gotLocalpart, err := db.GetLocalpartForThreePID(ctx, threePID, medium)
+		gotLocalpart, gotDomain, err := db.GetLocalpartForThreePID(ctx, threePID, medium)
 		assert.NoError(t, err, "unable to get localpart for threepid")
 		assert.Equal(t, aliceLocalpart, gotLocalpart)
+		assert.Equal(t, aliceDomain, gotDomain)
 
-		threepids, err := db.GetThreePIDsForLocalpart(ctx, aliceLocalpart)
+		threepids, err := db.GetThreePIDsForLocalpart(ctx, aliceLocalpart, aliceDomain)
 		assert.NoError(t, err, "unable to get threepids for localpart")
 		assert.Equal(t, 1, len(threepids))
 		assert.Equal(t, authtypes.ThreePID{
@@ -490,7 +494,7 @@ func Test_ThreePID(t *testing.T) {
 		assert.NoError(t, err, "unexpected error")
 
 		// verify it was deleted
-		threepids, err = db.GetThreePIDsForLocalpart(ctx, aliceLocalpart)
+		threepids, err = db.GetThreePIDsForLocalpart(ctx, aliceLocalpart, aliceDomain)
 		assert.NoError(t, err, "unable to get threepids for localpart")
 		assert.Equal(t, 0, len(threepids))
 	})
@@ -498,7 +502,7 @@ func Test_ThreePID(t *testing.T) {
 
 func Test_Notification(t *testing.T) {
 	alice := test.NewUser(t)
-	aliceLocalpart, _, err := gomatrixserverlib.SplitID('@', alice.ID)
+	aliceLocalpart, aliceDomain, err := gomatrixserverlib.SplitID('@', alice.ID)
 	assert.NoError(t, err)
 	room := test.NewRoom(t, alice)
 	room2 := test.NewRoom(t, alice)
@@ -526,34 +530,34 @@ func Test_Notification(t *testing.T) {
 				RoomID: roomID,
 				TS:     gomatrixserverlib.AsTimestamp(ts),
 			}
-			err = db.InsertNotification(ctx, aliceLocalpart, eventID, uint64(i+1), nil, notification)
+			err = db.InsertNotification(ctx, aliceLocalpart, aliceDomain, eventID, uint64(i+1), nil, notification)
 			assert.NoError(t, err, "unable to insert notification")
 		}
 
 		// get notifications
-		count, err := db.GetNotificationCount(ctx, aliceLocalpart, tables.AllNotifications)
+		count, err := db.GetNotificationCount(ctx, aliceLocalpart, aliceDomain, tables.AllNotifications)
 		assert.NoError(t, err, "unable to get notification count")
 		assert.Equal(t, int64(10), count)
-		notifs, count, err := db.GetNotifications(ctx, aliceLocalpart, 0, 15, tables.AllNotifications)
+		notifs, count, err := db.GetNotifications(ctx, aliceLocalpart, aliceDomain, 0, 15, tables.AllNotifications)
 		assert.NoError(t, err, "unable to get notifications")
 		assert.Equal(t, int64(10), count)
 		assert.Equal(t, 10, len(notifs))
 		// ... for a specific room
-		total, _, err := db.GetRoomNotificationCounts(ctx, aliceLocalpart, room2.ID)
+		total, _, err := db.GetRoomNotificationCounts(ctx, aliceLocalpart, aliceDomain, room2.ID)
 		assert.NoError(t, err, "unable to get notifications for room")
 		assert.Equal(t, int64(4), total)
 
 		// mark notification as read
-		affected, err := db.SetNotificationsRead(ctx, aliceLocalpart, room2.ID, 7, true)
+		affected, err := db.SetNotificationsRead(ctx, aliceLocalpart, aliceDomain, room2.ID, 7, true)
 		assert.NoError(t, err, "unable to set notifications read")
 		assert.True(t, affected)
 
 		// this should delete 2 notifications
-		affected, err = db.DeleteNotificationsUpTo(ctx, aliceLocalpart, room2.ID, 8)
+		affected, err = db.DeleteNotificationsUpTo(ctx, aliceLocalpart, aliceDomain, room2.ID, 8)
 		assert.NoError(t, err, "unable to set notifications read")
 		assert.True(t, affected)
 
-		total, _, err = db.GetRoomNotificationCounts(ctx, aliceLocalpart, room2.ID)
+		total, _, err = db.GetRoomNotificationCounts(ctx, aliceLocalpart, aliceDomain, room2.ID)
 		assert.NoError(t, err, "unable to get notifications for room")
 		assert.Equal(t, int64(2), total)
 
@@ -562,7 +566,7 @@ func Test_Notification(t *testing.T) {
 		assert.NoError(t, err)
 
 		// this should now return 0 notifications
-		total, _, err = db.GetRoomNotificationCounts(ctx, aliceLocalpart, room2.ID)
+		total, _, err = db.GetRoomNotificationCounts(ctx, aliceLocalpart, aliceDomain, room2.ID)
 		assert.NoError(t, err, "unable to get notifications for room")
 		assert.Equal(t, int64(0), total)
 	})
diff --git a/userapi/storage/tables/interface.go b/userapi/storage/tables/interface.go
index 5e1dd097..e14776cf 100644
--- a/userapi/storage/tables/interface.go
+++ b/userapi/storage/tables/interface.go
@@ -28,31 +28,31 @@ import (
 )
 
 type AccountDataTable interface {
-	InsertAccountData(ctx context.Context, txn *sql.Tx, localpart, roomID, dataType string, content json.RawMessage) error
-	SelectAccountData(ctx context.Context, localpart string) (map[string]json.RawMessage, map[string]map[string]json.RawMessage, error)
-	SelectAccountDataByType(ctx context.Context, localpart, roomID, dataType string) (data json.RawMessage, err error)
+	InsertAccountData(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, roomID, dataType string, content json.RawMessage) error
+	SelectAccountData(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName) (map[string]json.RawMessage, map[string]map[string]json.RawMessage, error)
+	SelectAccountDataByType(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, roomID, dataType string) (data json.RawMessage, err error)
 }
 
 type AccountsTable interface {
-	InsertAccount(ctx context.Context, txn *sql.Tx, localpart, hash, appserviceID string, accountType api.AccountType) (*api.Account, error)
-	UpdatePassword(ctx context.Context, localpart, passwordHash string) (err error)
-	DeactivateAccount(ctx context.Context, localpart string) (err error)
-	SelectPasswordHash(ctx context.Context, localpart string) (hash string, err error)
-	SelectAccountByLocalpart(ctx context.Context, localpart string) (*api.Account, error)
-	SelectNewNumericLocalpart(ctx context.Context, txn *sql.Tx) (id int64, err error)
+	InsertAccount(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, hash, appserviceID string, accountType api.AccountType) (*api.Account, error)
+	UpdatePassword(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, passwordHash string) (err error)
+	DeactivateAccount(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName) (err error)
+	SelectPasswordHash(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName) (hash string, err error)
+	SelectAccountByLocalpart(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName) (*api.Account, error)
+	SelectNewNumericLocalpart(ctx context.Context, txn *sql.Tx, serverName gomatrixserverlib.ServerName) (id int64, err error)
 }
 
 type DevicesTable interface {
-	InsertDevice(ctx context.Context, txn *sql.Tx, id, localpart, accessToken string, displayName *string, ipAddr, userAgent string) (*api.Device, error)
-	DeleteDevice(ctx context.Context, txn *sql.Tx, id, localpart string) error
-	DeleteDevices(ctx context.Context, txn *sql.Tx, localpart string, devices []string) error
-	DeleteDevicesByLocalpart(ctx context.Context, txn *sql.Tx, localpart, exceptDeviceID string) error
-	UpdateDeviceName(ctx context.Context, txn *sql.Tx, localpart, deviceID string, displayName *string) error
+	InsertDevice(ctx context.Context, txn *sql.Tx, id, localpart string, serverName gomatrixserverlib.ServerName, accessToken string, displayName *string, ipAddr, userAgent string) (*api.Device, error)
+	DeleteDevice(ctx context.Context, txn *sql.Tx, id, localpart string, serverName gomatrixserverlib.ServerName) error
+	DeleteDevices(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, devices []string) error
+	DeleteDevicesByLocalpart(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, exceptDeviceID string) error
+	UpdateDeviceName(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, deviceID string, displayName *string) error
 	SelectDeviceByToken(ctx context.Context, accessToken string) (*api.Device, error)
-	SelectDeviceByID(ctx context.Context, localpart, deviceID string) (*api.Device, error)
-	SelectDevicesByLocalpart(ctx context.Context, txn *sql.Tx, localpart, exceptDeviceID string) ([]api.Device, error)
+	SelectDeviceByID(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, deviceID string) (*api.Device, error)
+	SelectDevicesByLocalpart(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, exceptDeviceID string) ([]api.Device, error)
 	SelectDevicesByID(ctx context.Context, deviceIDs []string) ([]api.Device, error)
-	UpdateDeviceLastSeen(ctx context.Context, txn *sql.Tx, localpart, deviceID, ipAddr, userAgent string) error
+	UpdateDeviceLastSeen(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, deviceID, ipAddr, userAgent string) error
 }
 
 type KeyBackupTable interface {
@@ -79,40 +79,40 @@ type LoginTokenTable interface {
 }
 
 type OpenIDTable interface {
-	InsertOpenIDToken(ctx context.Context, txn *sql.Tx, token, localpart string, expiresAtMS int64) (err error)
+	InsertOpenIDToken(ctx context.Context, txn *sql.Tx, token, localpart string, serverName gomatrixserverlib.ServerName, expiresAtMS int64) (err error)
 	SelectOpenIDTokenAtrributes(ctx context.Context, token string) (*api.OpenIDTokenAttributes, error)
 }
 
 type ProfileTable interface {
-	InsertProfile(ctx context.Context, txn *sql.Tx, localpart string) error
-	SelectProfileByLocalpart(ctx context.Context, localpart string) (*authtypes.Profile, error)
-	SetAvatarURL(ctx context.Context, txn *sql.Tx, localpart string, avatarURL string) (*authtypes.Profile, bool, error)
-	SetDisplayName(ctx context.Context, txn *sql.Tx, localpart string, displayName string) (*authtypes.Profile, bool, error)
+	InsertProfile(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName) error
+	SelectProfileByLocalpart(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName) (*authtypes.Profile, error)
+	SetAvatarURL(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, avatarURL string) (*authtypes.Profile, bool, error)
+	SetDisplayName(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, displayName string) (*authtypes.Profile, bool, error)
 	SelectProfilesBySearch(ctx context.Context, searchString string, limit int) ([]authtypes.Profile, error)
 }
 
 type ThreePIDTable interface {
-	SelectLocalpartForThreePID(ctx context.Context, txn *sql.Tx, threepid string, medium string) (localpart string, err error)
-	SelectThreePIDsForLocalpart(ctx context.Context, localpart string) (threepids []authtypes.ThreePID, err error)
-	InsertThreePID(ctx context.Context, txn *sql.Tx, threepid, medium, localpart string) (err error)
+	SelectLocalpartForThreePID(ctx context.Context, txn *sql.Tx, threepid string, medium string) (localpart string, serverName gomatrixserverlib.ServerName, err error)
+	SelectThreePIDsForLocalpart(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName) (threepids []authtypes.ThreePID, err error)
+	InsertThreePID(ctx context.Context, txn *sql.Tx, threepid, medium, localpart string, serverName gomatrixserverlib.ServerName) (err error)
 	DeleteThreePID(ctx context.Context, txn *sql.Tx, threepid string, medium string) (err error)
 }
 
 type PusherTable interface {
-	InsertPusher(ctx context.Context, txn *sql.Tx, session_id int64, pushkey string, pushkeyTS int64, kind api.PusherKind, appid, appdisplayname, devicedisplayname, profiletag, lang, data, localpart string) error
-	SelectPushers(ctx context.Context, txn *sql.Tx, localpart string) ([]api.Pusher, error)
-	DeletePusher(ctx context.Context, txn *sql.Tx, appid, pushkey, localpart string) error
+	InsertPusher(ctx context.Context, txn *sql.Tx, session_id int64, pushkey string, pushkeyTS int64, kind api.PusherKind, appid, appdisplayname, devicedisplayname, profiletag, lang, data, localpart string, serverName gomatrixserverlib.ServerName) error
+	SelectPushers(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName) ([]api.Pusher, error)
+	DeletePusher(ctx context.Context, txn *sql.Tx, appid, pushkey, localpart string, serverName gomatrixserverlib.ServerName) error
 	DeletePushers(ctx context.Context, txn *sql.Tx, appid, pushkey string) error
 }
 
 type NotificationTable interface {
 	Clean(ctx context.Context, txn *sql.Tx) error
-	Insert(ctx context.Context, txn *sql.Tx, localpart, eventID string, pos uint64, highlight bool, n *api.Notification) error
-	DeleteUpTo(ctx context.Context, txn *sql.Tx, localpart, roomID string, pos uint64) (affected bool, _ error)
-	UpdateRead(ctx context.Context, txn *sql.Tx, localpart, roomID string, pos uint64, v bool) (affected bool, _ error)
-	Select(ctx context.Context, txn *sql.Tx, localpart string, fromID int64, limit int, filter NotificationFilter) ([]*api.Notification, int64, error)
-	SelectCount(ctx context.Context, txn *sql.Tx, localpart string, filter NotificationFilter) (int64, error)
-	SelectRoomCounts(ctx context.Context, txn *sql.Tx, localpart, roomID string) (total int64, highlight int64, _ error)
+	Insert(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, eventID string, pos uint64, highlight bool, n *api.Notification) error
+	DeleteUpTo(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, roomID string, pos uint64) (affected bool, _ error)
+	UpdateRead(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, roomID string, pos uint64, v bool) (affected bool, _ error)
+	Select(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, fromID int64, limit int, filter NotificationFilter) ([]*api.Notification, int64, error)
+	SelectCount(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, filter NotificationFilter) (int64, error)
+	SelectRoomCounts(ctx context.Context, txn *sql.Tx, localpart string, serverName gomatrixserverlib.ServerName, roomID string) (total int64, highlight int64, _ error)
 }
 
 type StatsTable interface {
diff --git a/userapi/storage/tables/stats_table_test.go b/userapi/storage/tables/stats_table_test.go
index a547423b..b088d15c 100644
--- a/userapi/storage/tables/stats_table_test.go
+++ b/userapi/storage/tables/stats_table_test.go
@@ -79,6 +79,7 @@ func mustMakeAccountAndDevice(
 	accDB tables.AccountsTable,
 	devDB tables.DevicesTable,
 	localpart string,
+	serverName gomatrixserverlib.ServerName, // nolint:unparam
 	accType api.AccountType,
 	userAgent string,
 ) {
@@ -89,11 +90,11 @@ func mustMakeAccountAndDevice(
 		appServiceID = util.RandomString(16)
 	}
 
-	_, err := accDB.InsertAccount(ctx, nil, localpart, "", appServiceID, accType)
+	_, err := accDB.InsertAccount(ctx, nil, localpart, serverName, "", appServiceID, accType)
 	if err != nil {
 		t.Fatalf("unable to create account: %v", err)
 	}
-	_, err = devDB.InsertDevice(ctx, nil, "deviceID", localpart, util.RandomString(16), nil, "", userAgent)
+	_, err = devDB.InsertDevice(ctx, nil, "deviceID", localpart, serverName, util.RandomString(16), nil, "", userAgent)
 	if err != nil {
 		t.Fatalf("unable to create device: %v", err)
 	}
@@ -150,12 +151,12 @@ func Test_UserStatistics(t *testing.T) {
 		})
 
 		t.Run("Want Users", func(t *testing.T) {
-			mustMakeAccountAndDevice(t, ctx, accDB, devDB, "user1", api.AccountTypeUser, "Element Android")
-			mustMakeAccountAndDevice(t, ctx, accDB, devDB, "user2", api.AccountTypeUser, "Element iOS")
-			mustMakeAccountAndDevice(t, ctx, accDB, devDB, "user3", api.AccountTypeUser, "Element web")
-			mustMakeAccountAndDevice(t, ctx, accDB, devDB, "user4", api.AccountTypeGuest, "Element Electron")
-			mustMakeAccountAndDevice(t, ctx, accDB, devDB, "user5", api.AccountTypeAdmin, "gecko")
-			mustMakeAccountAndDevice(t, ctx, accDB, devDB, "user6", api.AccountTypeAppService, "gecko")
+			mustMakeAccountAndDevice(t, ctx, accDB, devDB, "user1", "localhost", api.AccountTypeUser, "Element Android")
+			mustMakeAccountAndDevice(t, ctx, accDB, devDB, "user2", "localhost", api.AccountTypeUser, "Element iOS")
+			mustMakeAccountAndDevice(t, ctx, accDB, devDB, "user3", "localhost", api.AccountTypeUser, "Element web")
+			mustMakeAccountAndDevice(t, ctx, accDB, devDB, "user4", "localhost", api.AccountTypeGuest, "Element Electron")
+			mustMakeAccountAndDevice(t, ctx, accDB, devDB, "user5", "localhost", api.AccountTypeAdmin, "gecko")
+			mustMakeAccountAndDevice(t, ctx, accDB, devDB, "user6", "localhost", api.AccountTypeAppService, "gecko")
 			gotStats, _, err := statsDB.UserStatistics(ctx, nil)
 			if err != nil {
 				t.Fatalf("unexpected error: %v", err)
diff --git a/userapi/userapi_test.go b/userapi/userapi_test.go
index 2a43c0bd..23acfa6f 100644
--- a/userapi/userapi_test.go
+++ b/userapi/userapi_test.go
@@ -80,14 +80,14 @@ func TestQueryProfile(t *testing.T) {
 	// only one DBType, since userapi.AddInternalRoutes complains about multiple prometheus counters added
 	userAPI, accountDB, close := MustMakeInternalAPI(t, apiTestOpts{}, test.DBTypeSQLite)
 	defer close()
-	_, err := accountDB.CreateAccount(context.TODO(), "alice", "foobar", "", api.AccountTypeUser)
+	_, err := accountDB.CreateAccount(context.TODO(), "alice", serverName, "foobar", "", api.AccountTypeUser)
 	if err != nil {
 		t.Fatalf("failed to make account: %s", err)
 	}
-	if _, _, err := accountDB.SetAvatarURL(context.TODO(), "alice", aliceAvatarURL); err != nil {
+	if _, _, err := accountDB.SetAvatarURL(context.TODO(), "alice", serverName, aliceAvatarURL); err != nil {
 		t.Fatalf("failed to set avatar url: %s", err)
 	}
-	if _, _, err := accountDB.SetDisplayName(context.TODO(), "alice", aliceDisplayName); err != nil {
+	if _, _, err := accountDB.SetDisplayName(context.TODO(), "alice", serverName, aliceDisplayName); err != nil {
 		t.Fatalf("failed to set display name: %s", err)
 	}
 
@@ -164,7 +164,7 @@ func TestPasswordlessLoginFails(t *testing.T) {
 	test.WithAllDatabases(t, func(t *testing.T, dbType test.DBType) {
 		userAPI, accountDB, close := MustMakeInternalAPI(t, apiTestOpts{}, dbType)
 		defer close()
-		_, err := accountDB.CreateAccount(ctx, "auser", "", "", api.AccountTypeAppService)
+		_, err := accountDB.CreateAccount(ctx, "auser", serverName, "", "", api.AccountTypeAppService)
 		if err != nil {
 			t.Fatalf("failed to make account: %s", err)
 		}
@@ -190,7 +190,7 @@ func TestLoginToken(t *testing.T) {
 		test.WithAllDatabases(t, func(t *testing.T, dbType test.DBType) {
 			userAPI, accountDB, close := MustMakeInternalAPI(t, apiTestOpts{}, dbType)
 			defer close()
-			_, err := accountDB.CreateAccount(ctx, "auser", "apassword", "", api.AccountTypeUser)
+			_, err := accountDB.CreateAccount(ctx, "auser", serverName, "apassword", "", api.AccountTypeUser)
 			if err != nil {
 				t.Fatalf("failed to make account: %s", err)
 			}
diff --git a/userapi/util/devices.go b/userapi/util/devices.go
index cbf3bd28..c55fc799 100644
--- a/userapi/util/devices.go
+++ b/userapi/util/devices.go
@@ -2,10 +2,12 @@ package util
 
 import (
 	"context"
+	"fmt"
 
 	"github.com/matrix-org/dendrite/internal/pushgateway"
 	"github.com/matrix-org/dendrite/userapi/api"
 	"github.com/matrix-org/dendrite/userapi/storage"
+	"github.com/matrix-org/gomatrixserverlib"
 	log "github.com/sirupsen/logrus"
 )
 
@@ -17,10 +19,10 @@ type PusherDevice struct {
 }
 
 // GetPushDevices pushes to the configured devices of a local user.
-func GetPushDevices(ctx context.Context, localpart string, tweaks map[string]interface{}, db storage.Database) ([]*PusherDevice, error) {
-	pushers, err := db.GetPushers(ctx, localpart)
+func GetPushDevices(ctx context.Context, localpart string, serverName gomatrixserverlib.ServerName, tweaks map[string]interface{}, db storage.Database) ([]*PusherDevice, error) {
+	pushers, err := db.GetPushers(ctx, localpart, serverName)
 	if err != nil {
-		return nil, err
+		return nil, fmt.Errorf("db.GetPushers: %w", err)
 	}
 
 	devices := make([]*PusherDevice, 0, len(pushers))
diff --git a/userapi/util/notify.go b/userapi/util/notify.go
index ff206bd3..fc0ab39b 100644
--- a/userapi/util/notify.go
+++ b/userapi/util/notify.go
@@ -8,6 +8,7 @@ import (
 	"github.com/matrix-org/dendrite/internal/pushgateway"
 	"github.com/matrix-org/dendrite/userapi/storage"
 	"github.com/matrix-org/dendrite/userapi/storage/tables"
+	"github.com/matrix-org/gomatrixserverlib"
 	log "github.com/sirupsen/logrus"
 )
 
@@ -16,8 +17,8 @@ import (
 // a single goroutine is started when talking to the Push
 // gateways. There is no way to know when the background goroutine has
 // finished.
-func NotifyUserCountsAsync(ctx context.Context, pgClient pushgateway.Client, localpart string, db storage.Database) error {
-	pusherDevices, err := GetPushDevices(ctx, localpart, nil, db)
+func NotifyUserCountsAsync(ctx context.Context, pgClient pushgateway.Client, localpart string, serverName gomatrixserverlib.ServerName, db storage.Database) error {
+	pusherDevices, err := GetPushDevices(ctx, localpart, serverName, nil, db)
 	if err != nil {
 		return err
 	}
@@ -26,7 +27,7 @@ func NotifyUserCountsAsync(ctx context.Context, pgClient pushgateway.Client, loc
 		return nil
 	}
 
-	userNumUnreadNotifs, err := db.GetNotificationCount(ctx, localpart, tables.AllNotifications)
+	userNumUnreadNotifs, err := db.GetNotificationCount(ctx, localpart, serverName, tables.AllNotifications)
 	if err != nil {
 		return err
 	}