diff --git a/changelog.d/14874.bugfix b/changelog.d/14874.bugfix
new file mode 100644
index 000000000000..91ae2ea9bd5f
--- /dev/null
+++ b/changelog.d/14874.bugfix
@@ -0,0 +1 @@
+Faster joins: Fix a bug in worker deployments where the room stats and user directory would not get updated when finishing a fast join until another event is sent or received.
diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py
index 7620245e2642..321712786584 100644
--- a/synapse/handlers/federation.py
+++ b/synapse/handlers/federation.py
@@ -1880,9 +1880,10 @@ async def _sync_partial_state_room(
                         room_id
                     )
 
-                    # TODO(faster_joins) update room stats and user directory?
-                    #   https://github.com/matrix-org/synapse/issues/12814
-                    #   https://github.com/matrix-org/synapse/issues/12815
+                    # Poke the notifier so that other workers see the write to
+                    # the un-partial-stated rooms stream.
+                    self._notifier.notify_replication()
+
                     return
 
                 # we raced against more events arriving with partial state. Go round
diff --git a/synapse/replication/tcp/client.py b/synapse/replication/tcp/client.py
index 493f61667999..2a9cb499a48d 100644
--- a/synapse/replication/tcp/client.py
+++ b/synapse/replication/tcp/client.py
@@ -207,6 +207,12 @@ async def on_rdata(
             # we don't need to optimise this for multiple rows.
             for row in rows:
                 if row.type != EventsStreamEventRow.TypeId:
+                    # The row's data is an `EventsStreamCurrentStateRow`.
+                    # When we recompute the current state of a room based on forward
+                    # extremities (see `update_current_state`), no new events are
+                    # persisted, so we must poke the replication callbacks ourselves.
+                    # This functionality is used when finishing up a partial state join.
+                    self.notifier.notify_replication()
                     continue
                 assert isinstance(row, EventsStreamRow)
                 assert isinstance(row.data, EventsStreamEventRow)
diff --git a/synapse/storage/controllers/state.py b/synapse/storage/controllers/state.py
index 26d79c6e62f2..2045169b9a5d 100644
--- a/synapse/storage/controllers/state.py
+++ b/synapse/storage/controllers/state.py
@@ -493,8 +493,6 @@ async def get_current_state_deltas(
                  up to date.
         """
         # FIXME(faster_joins): what do we do here?
-        #   https://github.com/matrix-org/synapse/issues/12814
-        #   https://github.com/matrix-org/synapse/issues/12815
         #   https://github.com/matrix-org/synapse/issues/13008
 
         return await self.stores.main.get_partial_current_state_deltas(