diff --git a/gateway/channel_directory.py b/gateway/channel_directory.py
index da643ba146..23d6f361e1 100644
--- a/gateway/channel_directory.py
+++ b/gateway/channel_directory.py
@@ -206,7 +206,7 @@ async def build_channel_directory(adapters: Dict[Any, Any]) -> Dict[str, Any]:
     }
 
     try:
-        atomic_json_write(DIRECTORY_PATH, directory)
+        await asyncio.to_thread(atomic_json_write, DIRECTORY_PATH, directory)
     except Exception as e:
         logger.warning("Channel directory: failed to write: %s", e)