diff --git a/proposals/xxxx-remove-query_auth-federation-endpoint.md b/proposals/2451-remove-query_auth-federation-endpoint.md
similarity index 96%
rename from proposals/xxxx-remove-query_auth-federation-endpoint.md
rename to proposals/2451-remove-query_auth-federation-endpoint.md
index 387f2efa..d5c2af4d 100644
--- a/proposals/xxxx-remove-query_auth-federation-endpoint.md
+++ b/proposals/2451-remove-query_auth-federation-endpoint.md
@@ -1,4 +1,4 @@
-# MSCxxxx: Remove the `query_auth` federation endpoint
+# MSC2451: Remove the `query_auth` federation endpoint
 
 The `query_auth` federation endpoint is unused by Synapse and should be removed.
 The current implementation in Synapse is not robust and will return a 500 error