diff --git a/clientapi/routing/state.go b/clientapi/routing/state.go
index 359a3cca3..d74002928 100644
--- a/clientapi/routing/state.go
+++ b/clientapi/routing/state.go
@@ -140,23 +140,11 @@ func OnIncomingStateRequest(ctx context.Context, device *userapi.Device, rsAPI a
 		// use the result of the previous QueryLatestEventsAndState response
 		// to find the state event, if provided.
 		for _, ev := range stateRes.StateEvents {
-			sender := spec.UserID{}
-			userID, err := rsAPI.QueryUserIDForSender(ctx, ev.RoomID(), ev.SenderID())
-			if err == nil && userID != nil {
-				sender = *userID
-			}
-
-			sk := ev.StateKey()
-			if sk != nil && *sk != "" {
-				skUserID, err := rsAPI.QueryUserIDForSender(ctx, ev.RoomID(), spec.SenderID(*ev.StateKey()))
-				if err == nil && skUserID != nil {
-					skString := skUserID.String()
-					sk = &skString
-				}
-			}
 			stateEvents = append(
 				stateEvents,
-				synctypes.ToClientEvent(ev, synctypes.FormatAll, sender, sk),
+				synctypes.ToClientEventDefault(func(roomID string, senderID spec.SenderID) (*spec.UserID, error) {
+					return rsAPI.QueryUserIDForSender(ctx, roomID, senderID)
+				}, ev),
 			)
 		}
 	} else {
@@ -362,22 +350,10 @@ func OnIncomingStateTypeRequest(
 		}
 	}
 
-	sender := spec.UserID{}
-	userID, err := rsAPI.QueryUserIDForSender(ctx, event.RoomID(), event.SenderID())
-	if err == nil && userID != nil {
-		sender = *userID
-	}
-
-	sk := event.StateKey()
-	if sk != nil && *sk != "" {
-		skUserID, err := rsAPI.QueryUserIDForSender(ctx, event.RoomID(), spec.SenderID(*event.StateKey()))
-		if err == nil && skUserID != nil {
-			skString := skUserID.String()
-			sk = &skString
-		}
-	}
 	stateEvent := stateEventInStateResp{
-		ClientEvent: synctypes.ToClientEvent(event, synctypes.FormatAll, sender, sk),
+		ClientEvent: synctypes.ToClientEventDefault(func(roomID string, senderID spec.SenderID) (*spec.UserID, error) {
+			return rsAPI.QueryUserIDForSender(ctx, roomID, senderID)
+		}, event),
 	}
 
 	var res interface{}
diff --git a/roomserver/internal/query/query.go b/roomserver/internal/query/query.go
index a1dde341b..08af41c1e 100644
--- a/roomserver/internal/query/query.go
+++ b/roomserver/internal/query/query.go
@@ -388,21 +388,9 @@ func (r *Queryer) QueryMembershipsForRoom(
 			return fmt.Errorf("r.DB.Events: %w", err)
 		}
 		for _, event := range events {
-			sender := spec.UserID{}
-			userID, queryErr := r.QueryUserIDForSender(ctx, event.RoomID(), event.SenderID())
-			if queryErr == nil && userID != nil {
-				sender = *userID
-			}
-
-			sk := event.StateKey()
-			if sk != nil && *sk != "" {
-				skUserID, err := r.QueryUserIDForSender(ctx, event.RoomID(), spec.SenderID(*event.StateKey()))
-				if err == nil && skUserID != nil {
-					skString := skUserID.String()
-					sk = &skString
-				}
-			}
-			clientEvent := synctypes.ToClientEvent(event.PDU, synctypes.FormatAll, sender, sk)
+			clientEvent := synctypes.ToClientEventDefault(func(roomID string, senderID spec.SenderID) (*spec.UserID, error) {
+				return r.QueryUserIDForSender(ctx, roomID, senderID)
+			}, event)
 			response.JoinEvents = append(response.JoinEvents, clientEvent)
 		}
 		return nil
@@ -451,21 +439,9 @@ func (r *Queryer) QueryMembershipsForRoom(
 	}
 
 	for _, event := range events {
-		sender := spec.UserID{}
-		userID, err := r.QueryUserIDForSender(ctx, event.RoomID(), event.SenderID())
-		if err == nil && userID != nil {
-			sender = *userID
-		}
-
-		sk := event.StateKey()
-		if sk != nil && *sk != "" {
-			skUserID, err := r.QueryUserIDForSender(ctx, event.RoomID(), spec.SenderID(*event.StateKey()))
-			if err == nil && skUserID != nil {
-				skString := skUserID.String()
-				sk = &skString
-			}
-		}
-		clientEvent := synctypes.ToClientEvent(event.PDU, synctypes.FormatAll, sender, sk)
+		clientEvent := synctypes.ToClientEventDefault(func(roomID string, senderID spec.SenderID) (*spec.UserID, error) {
+			return r.QueryUserIDForSender(ctx, roomID, senderID)
+		}, event)
 		response.JoinEvents = append(response.JoinEvents, clientEvent)
 	}
 
diff --git a/syncapi/routing/context.go b/syncapi/routing/context.go
index d402e468c..144baff1e 100644
--- a/syncapi/routing/context.go
+++ b/syncapi/routing/context.go
@@ -217,21 +217,9 @@ func Context(
 		}
 	}
 
-	sender := spec.UserID{}
-	userID, err := rsAPI.QueryUserIDForSender(ctx, requestedEvent.RoomID(), requestedEvent.SenderID())
-	if err == nil && userID != nil {
-		sender = *userID
-	}
-
-	sk := requestedEvent.StateKey()
-	if sk != nil && *sk != "" {
-		skUserID, err := rsAPI.QueryUserIDForSender(ctx, requestedEvent.RoomID(), spec.SenderID(*requestedEvent.StateKey()))
-		if err == nil && skUserID != nil {
-			skString := skUserID.String()
-			sk = &skString
-		}
-	}
-	ev := synctypes.ToClientEvent(&requestedEvent, synctypes.FormatAll, sender, sk)
+	ev := synctypes.ToClientEventDefault(func(roomID string, senderID spec.SenderID) (*spec.UserID, error) {
+		return rsAPI.QueryUserIDForSender(ctx, roomID, senderID)
+	}, requestedEvent)
 	response := ContextRespsonse{
 		Event:        &ev,
 		EventsAfter:  eventsAfterClient,
diff --git a/syncapi/synctypes/clientevent.go b/syncapi/synctypes/clientevent.go
index 06f52175b..358a0c971 100644
--- a/syncapi/synctypes/clientevent.go
+++ b/syncapi/synctypes/clientevent.go
@@ -86,3 +86,23 @@ func ToClientEvent(se gomatrixserverlib.PDU, format ClientEventFormat, sender sp
 	}
 	return ce
 }
+
+// ToClientEvent converts a single server event to a client event.
+// It provides default logic for event.SenderID & event.StateKey -> userID conversions.
+func ToClientEventDefault(userIDQuery spec.UserIDForSender, event gomatrixserverlib.PDU) ClientEvent {
+	sender := spec.UserID{}
+	userID, err := userIDQuery(event.RoomID(), event.SenderID())
+	if err == nil && userID != nil {
+		sender = *userID
+	}
+
+	sk := event.StateKey()
+	if sk != nil && *sk != "" {
+		skUserID, err := userIDQuery(event.RoomID(), spec.SenderID(*event.StateKey()))
+		if err == nil && skUserID != nil {
+			skString := skUserID.String()
+			sk = &skString
+		}
+	}
+	return ToClientEvent(event, FormatAll, sender, sk)
+}
diff --git a/userapi/consumers/roomserver.go b/userapi/consumers/roomserver.go
index bf63c69dc..a293b0850 100644
--- a/userapi/consumers/roomserver.go
+++ b/userapi/consumers/roomserver.go
@@ -309,8 +309,8 @@ func (s *OutputRoomEventConsumer) processMessage(ctx context.Context, event *rst
 
 		sk := event.StateKey()
 		if sk != nil && *sk != "" {
-			skUserID, err := s.rsAPI.QueryUserIDForSender(ctx, event.RoomID(), spec.SenderID(*event.StateKey()))
-			if err == nil && skUserID != nil {
+			skUserID, queryErr := s.rsAPI.QueryUserIDForSender(ctx, event.RoomID(), spec.SenderID(*event.StateKey()))
+			if queryErr == nil && skUserID != nil {
 				skString := skUserID.String()
 				sk = &skString
 			}
@@ -551,8 +551,8 @@ func (s *OutputRoomEventConsumer) notifyLocal(ctx context.Context, event *rstype
 
 	sk := event.StateKey()
 	if sk != nil && *sk != "" {
-		skUserID, err := s.rsAPI.QueryUserIDForSender(ctx, event.RoomID(), spec.SenderID(*event.StateKey()))
-		if err == nil && skUserID != nil {
+		skUserID, queryErr := s.rsAPI.QueryUserIDForSender(ctx, event.RoomID(), spec.SenderID(*event.StateKey()))
+		if queryErr == nil && skUserID != nil {
 			skString := skUserID.String()
 			sk = &skString
 		}