diff --git a/frontend/src/App.tsx b/frontend/src/App.tsx
index 8faabac5..a1347b5a 100644
--- a/frontend/src/App.tsx
+++ b/frontend/src/App.tsx
@@ -463,6 +463,13 @@ const AppContent: React.FC = () => {
     return <LoadingScreen />;
   }
 
+  // RULE: Business users on platform subdomain should be redirected to their business subdomain
+  if (isBusinessUser && isPlatformDomain && user.business_subdomain) {
+    const port = window.location.port ? `:${window.location.port}` : '';
+    window.location.href = `${protocol}//${user.business_subdomain}.${baseDomain}${port}/`;
+    return <LoadingScreen />;
+  }
+
   // RULE: Business users must be on their own business subdomain
   if (isBusinessUser && isBusinessSubdomain && user.business_subdomain && user.business_subdomain !== currentSubdomain) {
     const port = window.location.port ? `:${window.location.port}` : '';