diff --git a/src/service/rooms/alias/data.rs b/src/service/rooms/alias/data.rs
index eb99e543..302c21ae 100644
--- a/src/service/rooms/alias/data.rs
+++ b/src/service/rooms/alias/data.rs
@@ -84,7 +84,7 @@ impl Data {
 
 	pub(super) fn local_aliases_for_room<'a>(
 		&'a self, room_id: &RoomId,
-	) -> Box<dyn Iterator<Item = Result<OwnedRoomAliasId>> + 'a> {
+	) -> Box<dyn Iterator<Item = Result<OwnedRoomAliasId>> + 'a + Send> {
 		let mut prefix = room_id.as_bytes().to_vec();
 		prefix.push(0xFF);
 
diff --git a/src/service/rooms/alias/mod.rs b/src/service/rooms/alias/mod.rs
index 706bf2f8..4af1035e 100644
--- a/src/service/rooms/alias/mod.rs
+++ b/src/service/rooms/alias/mod.rs
@@ -97,7 +97,7 @@ impl Service {
 	#[tracing::instrument(skip(self), level = "debug")]
 	pub fn local_aliases_for_room<'a>(
 		&'a self, room_id: &RoomId,
-	) -> Box<dyn Iterator<Item = Result<OwnedRoomAliasId>> + 'a> {
+	) -> Box<dyn Iterator<Item = Result<OwnedRoomAliasId>> + 'a + Send> {
 		self.db.local_aliases_for_room(room_id)
 	}