diff --git a/synapse/api/auth.py b/synapse/api/auth.py
index a04be32890f3..79e2808dc5a7 100644
--- a/synapse/api/auth.py
+++ b/synapse/api/auth.py
@@ -196,7 +196,7 @@ def get_user_by_req(
         Args:
             request - An HTTP request with an access_token query parameter.
             allow_expired - Whether to allow the request through even if the account is
-                expired. If true, Synapse will still require the access token to be
+                expired. If true, Synapse will still require an access token to be
                 provided but won't check if the account it belongs to has expired. This
                 works thanks to /login delivering access tokens regardless of accounts'
                 expiration.