diff --git a/synapse/rest/client/versions.py b/synapse/rest/client/versions.py
index 2e9e16a6ba..c25fc5dbd4 100644
--- a/synapse/rest/client/versions.py
+++ b/synapse/rest/client/versions.py
@@ -133,7 +133,7 @@ class VersionsRestServlet(RestServlet):
                     # Supports receiving private read receipts as per MSC2285
                     "org.matrix.msc2285.stable": True,  # TODO: Remove when MSC2285 becomes a part of the spec
                     # Supports room previews as per MSC3266
-                    "org.matrix.msc3266": self.config.experimental.msc3266_enabled,
+                    "im.nheko.msc3266": self.config.experimental.msc3266_enabled,
                     # Supports filtering of /publicRooms by room type as per MSC3827
                     "org.matrix.msc3827.stable": True,
                     # Adds support for thread relations, per MSC3440.