diff --git a/src/main.jsx b/src/main.jsx
index 3cbbb29..30681bd 100644
--- a/src/main.jsx
+++ b/src/main.jsx
@@ -6,6 +6,12 @@ import './i18n';
 import { QueryClientProvider } from '@tanstack/react-query';
 import { queryClient } from './lib/queryClient';
 import './index.css';
+import { getLegacyRedirectUrl } from './utils/legacyHostRedirect';
+
+const legacyRedirectUrl = getLegacyRedirectUrl(globalThis?.location);
+if (legacyRedirectUrl) {
+  globalThis.location.replace(legacyRedirectUrl);
+}
 
 // Show [DEV] in the browser tab when running locally.
 const isLocalHost = ['localhost', '127.0.0.1', '0.0.0.0'].includes(globalThis?.location?.hostname);
@@ -27,17 +33,19 @@ if (import.meta.env.DEV && typeof navigator !== 'undefined' && 'serviceWorker' i
   }
 }
 
-ReactDOM.createRoot(document.getElementById('root')).render(
-  <React.StrictMode>
-    <QueryClientProvider client={queryClient}>
-      <BrowserRouter
-        future={{
-          v7_startTransition: true,
-          v7_relativeSplatPath: true,
-        }}
-      >
-        <App />
-      </BrowserRouter>
-    </QueryClientProvider>
-  </React.StrictMode>,
-);
+if (!legacyRedirectUrl) {
+  ReactDOM.createRoot(document.getElementById('root')).render(
+    <React.StrictMode>
+      <QueryClientProvider client={queryClient}>
+        <BrowserRouter
+          future={{
+            v7_startTransition: true,
+            v7_relativeSplatPath: true,
+          }}
+        >
+          <App />
+        </BrowserRouter>
+      </QueryClientProvider>
+    </React.StrictMode>,
+  );
+}
diff --git a/src/utils/legacyHostRedirect.js b/src/utils/legacyHostRedirect.js
new file mode 100644
index 0000000..9d97ee2
--- /dev/null
+++ b/src/utils/legacyHostRedirect.js
@@ -0,0 +1,9 @@
+const LEGACY_HOSTS = ['winbit-6579c.web.app', 'winbit-6579c.firebaseapp.com'];
+const CURRENT_ORIGIN = 'https://app.winbit.com.ar';
+
+// `/__/` is reserved by Firebase Hosting (Google sign-in handler); never redirect it.
+export const getLegacyRedirectUrl = ({ hostname, pathname = '/', search = '', hash = '' } = {}) => {
+  if (!LEGACY_HOSTS.includes(hostname)) return null;
+  if (pathname.startsWith('/__/')) return null;
+  return `${CURRENT_ORIGIN}${pathname}${search}${hash}`;
+};
diff --git a/src/utils/legacyHostRedirect.test.js b/src/utils/legacyHostRedirect.test.js
new file mode 100644
index 0000000..ce0b8b3
--- /dev/null
+++ b/src/utils/legacyHostRedirect.test.js
@@ -0,0 +1,42 @@
+import { describe, it, expect } from 'vitest';
+import { getLegacyRedirectUrl } from './legacyHostRedirect';
+
+describe('getLegacyRedirectUrl', () => {
+  it('redirects the legacy web.app host to the current domain', () => {
+    expect(getLegacyRedirectUrl({ hostname: 'winbit-6579c.web.app', pathname: '/' })).toBe(
+      'https://app.winbit.com.ar/',
+    );
+  });
+
+  it('redirects the legacy firebaseapp.com host', () => {
+    expect(
+      getLegacyRedirectUrl({ hostname: 'winbit-6579c.firebaseapp.com', pathname: '/login' }),
+    ).toBe('https://app.winbit.com.ar/login');
+  });
+
+  it('preserves path, query string and hash', () => {
+    expect(
+      getLegacyRedirectUrl({
+        hostname: 'winbit-6579c.web.app',
+        pathname: '/history',
+        search: '?tab=2',
+        hash: '#top',
+      }),
+    ).toBe('https://app.winbit.com.ar/history?tab=2#top');
+  });
+
+  it('never redirects the Firebase reserved /__/ paths', () => {
+    expect(
+      getLegacyRedirectUrl({
+        hostname: 'winbit-6579c.firebaseapp.com',
+        pathname: '/__/auth/handler',
+      }),
+    ).toBeNull();
+  });
+
+  it('does not redirect the current domain or local hosts', () => {
+    expect(getLegacyRedirectUrl({ hostname: 'app.winbit.com.ar', pathname: '/' })).toBeNull();
+    expect(getLegacyRedirectUrl({ hostname: 'localhost', pathname: '/' })).toBeNull();
+    expect(getLegacyRedirectUrl()).toBeNull();
+  });
+});