diff --git a/apps/web/src/routes/__root.tsx b/apps/web/src/routes/__root.tsx
index 0831a922325e..63495ce5cd65 100644
--- a/apps/web/src/routes/__root.tsx
+++ b/apps/web/src/routes/__root.tsx
@@ -3,6 +3,7 @@ import { scopedProjectKey, scopeProjectRef } from "@t3tools/client-runtime/envir
 import { squashAtomCommandFailure } from "@t3tools/client-runtime/state/runtime";
 import {
   Outlet,
+  Link,
   redirect,
   createRootRoute,
   type ErrorComponentProps,
@@ -104,11 +105,27 @@ export const Route = createRootRoute({
   },
   component: RootRouteView,
   errorComponent: RootRouteErrorView,
+  notFoundComponent: RootRouteNotFoundView,
   head: () => ({
     meta: [{ name: "title", content: APP_DISPLAY_NAME }],
   }),
 });
 
+function RootRouteNotFoundView() {
+  return (
+    <main className="flex min-h-0 min-w-0 flex-1 items-center justify-center p-6">
+      <div className="flex max-w-sm flex-col items-center gap-4 text-center">
+        <h1 className="text-lg font-medium text-foreground">Page not found</h1>
+        <p className="text-sm text-muted-foreground">
+          This link doesn't point to a page in {APP_DISPLAY_NAME}. Go home to choose a project or
+          start a thread.
+        </p>
+        <Button render={<Link to="/" replace />}>Go home</Button>
+      </div>
+    </main>
+  );
+}
+
 function RootRouteView() {
   useEffect(() => installDesktopPasteAsText(window.desktopBridge, window), []);
   const pathname = useLocation({ select: (location) => location.pathname });