diff --git a/synapse/storage/roommember.py b/synapse/storage/roommember.py
index c3e11b91da59f0db114c71b016f03c4ecee35165..d32ce1ab1e84612af6e8d751b419aa8d6b72196d 100644
--- a/synapse/storage/roommember.py
+++ b/synapse/storage/roommember.py
@@ -160,7 +160,7 @@ class RoomMemberStore(SQLBaseStore):
 
     def _get_rooms_for_user_where_membership_is_txn(self, txn, user_id,
                                                     membership_list):
-        where_clause = "user_id = ? AND (%s)" % (
+        where_clause = "user_id = ? AND (%s) AND NOT forgotten" % (
             " OR ".join(["membership = ?" for _ in membership_list]),
         )