diff --git a/packages/api/src/utils/usernamePolicy.ts b/packages/api/src/utils/usernamePolicy.ts
index f07383ecf..5b618e20e 100644
--- a/packages/api/src/utils/usernamePolicy.ts
+++ b/packages/api/src/utils/usernamePolicy.ts
@@ -123,6 +123,7 @@ const RESERVED_NAMES = new Set([
   'save',
   'search',
   'security',
+  'security.txt',
   'sessions',
   'settings',
   'shop',