diff --git a/packages/stack/src/lib/stack-app.ts b/packages/stack/src/lib/stack-app.ts
index 37a8233c79..9cafd75b67 100644
--- a/packages/stack/src/lib/stack-app.ts
+++ b/packages/stack/src/lib/stack-app.ts
@@ -2305,7 +2305,7 @@ type Auth = {
 type BaseUser = {
   readonly id: string,
 
-  readonly displayName: string | null,
+  readonly displayName: string,
 
   /**
    * The user's email address.