diff --git a/synapse/handlers/room.py b/synapse/handlers/room.py
index bec113fcc3..08db519f48 100644
--- a/synapse/handlers/room.py
+++ b/synapse/handlers/room.py
@@ -560,6 +560,14 @@ class RoomCreationHandler(BaseHandler):
 
         yield self.event_creation_handler.assert_accepted_privacy_policy(requester)
 
+        power_level_content_override = config.get("power_level_content_override")
+        if power_level_content_override and user_id not in power_level_content_override["users"]:
+            raise SynapseError(
+                400,
+                "Not a valid power_level_content_override, did not contain %s"
+                % (user_id,),
+            )
+
         invite_3pid_list = config.get("invite_3pid", [])
 
         visibility = config.get("visibility", None)
@@ -604,7 +612,7 @@ class RoomCreationHandler(BaseHandler):
             initial_state=initial_state,
             creation_content=creation_content,
             room_alias=room_alias,
-            power_level_content_override=config.get("power_level_content_override"),
+            power_level_content_override=power_level_content_override,
             creator_join_profile=creator_join_profile,
         )
 
@@ -752,13 +760,6 @@ class RoomCreationHandler(BaseHandler):
             if power_level_content_override:
                 power_level_content.update(power_level_content_override)
 
-            if creator_id not in power_level_content["users"]:
-                raise SynapseError(
-                    400,
-                    "Not a valid power_level_content_override, did not contain %s"
-                    % (creator_id,),
-                )
-
             yield send(etype=EventTypes.PowerLevels, content=power_level_content)
 
         if room_alias and (EventTypes.CanonicalAlias, "") not in initial_state: