diff --git a/synapse/handlers/profile.py b/synapse/handlers/profile.py
index dbff28e7fb..af5c55d2cd 100644
--- a/synapse/handlers/profile.py
+++ b/synapse/handlers/profile.py
@@ -20,7 +20,7 @@
 #
 import logging
 import random
-from typing import TYPE_CHECKING, List, Optional, Union
+from typing import TYPE_CHECKING, List, Optional, Tuple, Union
 
 from synapse.api.constants import ProfileFields
 from synapse.api.errors import (
@@ -32,7 +32,18 @@ from synapse.api.errors import (
     SynapseError,
 )
 from synapse.storage.databases.main.media_repository import LocalMedia, RemoteMedia
-from synapse.types import JsonDict, JsonValue, Requester, UserID, create_requester
+
+from synapse.types import (
+    JsonDict,
+    JsonMapping,
+    JsonValue
+    Requester,
+    ScheduledTask,
+    TaskStatus,
+    UserID,
+    create_requester,
+)
+
 from synapse.util.caches.descriptors import cached
 from synapse.util.stringutils import parse_and_validate_mxc_uri
 
@@ -46,6 +57,8 @@ MAX_AVATAR_URL_LEN = 1000
 # Field name length is specced at 255 bytes.
 MAX_CUSTOM_FIELD_LEN = 255
 
+UPDATE_JOIN_STATES_TASK_NAME = "update_join_states"
+
 
 class ProfileHandler:
     """Handles fetching and updating user profile information.
@@ -77,6 +90,11 @@ class ProfileHandler:
 
         self._third_party_rules = hs.get_module_api_callbacks().third_party_event_rules
 
+        self._task_scheduler = hs.get_task_scheduler()
+        self._task_scheduler.register_action(
+            self._update_join_states, UPDATE_JOIN_STATES_TASK_NAME
+        )
+
     async def get_profile(self, user_id: str, ignore_backoff: bool = True) -> JsonDict:
         """
         Get a user's profile as a JSON dictionary.
@@ -236,7 +254,13 @@ class ProfileHandler:
         )
 
         if propagate:
-            await self._update_join_states(requester, target_user)
+            await self._task_scheduler.schedule_task(
+                UPDATE_JOIN_STATES_TASK_NAME,
+                params={
+                    "requester": requester.serialize(),
+                    "target_user": target_user.to_string(),
+                },
+            )
 
     async def get_avatar_url(self, target_user: UserID) -> Optional[str]:
         """
@@ -338,7 +362,13 @@ class ProfileHandler:
         )
 
         if propagate:
-            await self._update_join_states(requester, target_user)
+            await self._task_scheduler.schedule_task(
+                UPDATE_JOIN_STATES_TASK_NAME,
+                params={
+                    "requester": requester.serialize(),
+                    "target_user": target_user.to_string(),
+                },
+            )
 
     @cached()
     async def check_avatar_size_and_mime_type(self, mxc: str) -> bool:
@@ -567,16 +597,26 @@ class ProfileHandler:
         return response
 
     async def _update_join_states(
-        self, requester: Requester, target_user: UserID
-    ) -> None:
+        self, task: ScheduledTask
+    ) -> Tuple[TaskStatus, Optional[JsonMapping], Optional[str]]:
         """
         Update the membership events of each room the user is joined to with the
         new profile information.
 
         Note that this stomps over any custom display name or avatar URL in member events.
+
+        Args:
+            target_user: The owner of the queried profile. This is a str rather
+            than a UserID because the task_scheduler requires JSON serializable
+            parameters
+            requester: The user querying for the profile.
         """
+        assert task.params is not None
+        requester = Requester.deserialize(self.store, task.params["requester"])
+        target_user = UserID.from_string(task.params["target_user"])
+
         if not self.hs.is_mine(target_user):
-            return
+            return TaskStatus.COMPLETE, None, None
 
         await self.request_ratelimiter.ratelimit(requester)
 
@@ -584,7 +624,7 @@ class ProfileHandler:
         if requester.shadow_banned:
             # We randomly sleep a bit just to annoy the requester.
             await self.clock.sleep(random.randint(1, 10))
-            return
+            return TaskStatus.COMPLETE, None, None
 
         room_ids = await self.store.get_rooms_for_user(target_user.to_string())
 
@@ -604,6 +644,7 @@ class ProfileHandler:
                 logger.warning(
                     "Failed to update join event for room %s - %s", room_id, str(e)
                 )
+        return TaskStatus.COMPLETE, None, None
 
     async def check_profile_query_allowed(
         self, target_user: UserID, requester: Optional[UserID] = None