diff --git a/changelog.d/13370.feature b/changelog.d/13370.feature
new file mode 100644
index 000000000000..3a49bc277868
--- /dev/null
+++ b/changelog.d/13370.feature
@@ -0,0 +1 @@
+Use stable prefixes for [MSC3827](https://github.com/matrix-org/matrix-spec-proposals/pull/3827).
diff --git a/synapse/api/constants.py b/synapse/api/constants.py
index 265376411907..789859e69ef8 100644
--- a/synapse/api/constants.py
+++ b/synapse/api/constants.py
@@ -268,4 +268,4 @@ class PublicRoomsFilterFields:
     """
 
     GENERIC_SEARCH_TERM: Final = "generic_search_term"
-    ROOM_TYPES: Final = "org.matrix.msc3827.room_types"
+    ROOM_TYPES: Final = "room_types"
diff --git a/synapse/config/experimental.py b/synapse/config/experimental.py
index 1902222d7b67..c2ecd977cd20 100644
--- a/synapse/config/experimental.py
+++ b/synapse/config/experimental.py
@@ -88,8 +88,5 @@ def read_config(self, config: JsonDict, **kwargs: Any) -> None:
         # MSC3715: dir param on /relations.
         self.msc3715_enabled: bool = experimental.get("msc3715_enabled", False)
 
-        # MSC3827: Filtering of /publicRooms by room type
-        self.msc3827_enabled: bool = experimental.get("msc3827_enabled", False)
-
         # MSC3848: Introduce errcodes for specific event sending failures
         self.msc3848_enabled: bool = experimental.get("msc3848_enabled", False)
diff --git a/synapse/handlers/room_list.py b/synapse/handlers/room_list.py
index 29868eb74311..bb0bdb8e6f39 100644
--- a/synapse/handlers/room_list.py
+++ b/synapse/handlers/room_list.py
@@ -182,7 +182,7 @@ def build_room_entry(room: JsonDict) -> JsonDict:
                 == HistoryVisibility.WORLD_READABLE,
                 "guest_can_join": room["guest_access"] == "can_join",
                 "join_rule": room["join_rules"],
-                "org.matrix.msc3827.room_type": room["room_type"],
+                "room_type": room["room_type"],
             }
 
             # Filter out Nones – rather omit the field altogether
diff --git a/synapse/rest/client/versions.py b/synapse/rest/client/versions.py
index f4f06563dddf..0366986755a2 100644
--- a/synapse/rest/client/versions.py
+++ b/synapse/rest/client/versions.py
@@ -95,8 +95,8 @@ def on_GET(self, request: Request) -> Tuple[int, JsonDict]:
                     "org.matrix.msc3026.busy_presence": self.config.experimental.msc3026_enabled,
                     # Supports receiving private read receipts as per MSC2285
                     "org.matrix.msc2285": self.config.experimental.msc2285_enabled,
-                    # Supports filtering of /publicRooms by room type MSC3827
-                    "org.matrix.msc3827": self.config.experimental.msc3827_enabled,
+                    # Supports filtering of /publicRooms by room type as per MSC3827
+                    "org.matrix.msc3827.stable": True,
                     # Adds support for importing historical messages as per MSC2716
                     "org.matrix.msc2716": self.config.experimental.msc2716_enabled,
                     # Adds support for jump to date endpoints (/timestamp_to_event) as per MSC3030
diff --git a/synapse/storage/databases/main/room.py b/synapse/storage/databases/main/room.py
index d6d485507b17..0f1f0d11eac6 100644
--- a/synapse/storage/databases/main/room.py
+++ b/synapse/storage/databases/main/room.py
@@ -207,7 +207,7 @@ async def get_public_room_ids(self) -> List[str]:
     def _construct_room_type_where_clause(
         self, room_types: Union[List[Union[str, None]], None]
     ) -> Tuple[Union[str, None], List[str]]:
-        if not room_types or not self.config.experimental.msc3827_enabled:
+        if not room_types:
             return None, []
         else:
             # We use None when we want get rooms without a type
diff --git a/tests/rest/client/test_rooms.py b/tests/rest/client/test_rooms.py
index 2272d55d84ec..aa2f57844120 100644
--- a/tests/rest/client/test_rooms.py
+++ b/tests/rest/client/test_rooms.py
@@ -2070,7 +2070,6 @@ def make_homeserver(self, reactor: MemoryReactor, clock: Clock) -> HomeServer:
 
         config = self.default_config()
         config["allow_public_rooms_without_auth"] = True
-        config["experimental_features"] = {"msc3827_enabled": True}
         self.hs = self.setup_test_homeserver(config=config)
         self.url = b"/_matrix/client/r0/publicRooms"
 
@@ -2123,13 +2122,13 @@ def test_returns_only_rooms_based_on_filter(self) -> None:
         chunk, count = self.make_public_rooms_request([None])
 
         self.assertEqual(count, 1)
-        self.assertEqual(chunk[0].get("org.matrix.msc3827.room_type", None), None)
+        self.assertEqual(chunk[0].get("room_type", None), None)
 
     def test_returns_only_space_based_on_filter(self) -> None:
         chunk, count = self.make_public_rooms_request(["m.space"])
 
         self.assertEqual(count, 1)
-        self.assertEqual(chunk[0].get("org.matrix.msc3827.room_type", None), "m.space")
+        self.assertEqual(chunk[0].get("room_type", None), "m.space")
 
     def test_returns_both_rooms_and_space_based_on_filter(self) -> None:
         chunk, count = self.make_public_rooms_request(["m.space", None])