diff --git a/tests/rest/test_well_known.py b/tests/rest/test_well_known.py
index 377243a1706d..1f04bec0679b 100644
--- a/tests/rest/test_well_known.py
+++ b/tests/rest/test_well_known.py
@@ -131,6 +131,7 @@ def test_client_well_known_msc3861_oauth_delegation(self) -> None:
             channel.json_body,
             {
                 "m.homeserver": {"base_url": "https://homeserver/"},
+                "m.identity_server": {"base_url": ""},
                 "org.matrix.msc2965.authentication": {
                     "issuer": "https://issuer",
                     "account": "https://my-account.issuer",