diff --git a/config.sample.json b/config.sample.json
index 5aa0a4bb0..c9a090aa9 100644
--- a/config.sample.json
+++ b/config.sample.json
@@ -25,5 +25,6 @@
   "noEncryptionWarningShown": false,
   "displayChatDetailsColumn": false,
   "colorSchemeSeedInt": 4283835834,
-  "enableSoftLogout": false
+  "enableSoftLogout": false,
+  "autoSsoRedirect": false
 }
\ No newline at end of file
diff --git a/lib/config/routes.dart b/lib/config/routes.dart
index 60e788786..19fa47902 100644
--- a/lib/config/routes.dart
+++ b/lib/config/routes.dart
@@ -5,6 +5,7 @@ import 'package:flutter/material.dart';
 import 'package:go_router/go_router.dart';
 import 'package:matrix/matrix.dart';
 
+import 'package:fluffychat/config/setting_keys.dart';
 import 'package:fluffychat/config/themes.dart';
 import 'package:fluffychat/pages/archive/archive.dart';
 import 'package:fluffychat/pages/bootstrap/bootstrap_dialog.dart';
@@ -63,6 +64,8 @@ abstract class AppRoutes {
       redirect: (context, state) =>
           Matrix.of(context).widget.clients.any((client) => client.isLogged())
           ? '/rooms'
+          : AppSettings.autoSsoRedirect.value
+          ? '/home/sign_in'
           : '/home',
     ),
     GoRoute(
diff --git a/lib/config/setting_keys.dart b/lib/config/setting_keys.dart
index 7011e8645..03d5cd8a5 100644
--- a/lib/config/setting_keys.dart
+++ b/lib/config/setting_keys.dart
@@ -52,7 +52,8 @@ enum AppSettings<T> {
   // colorSchemeSeed stored as ARGB int
   colorSchemeSeedInt<int>('chat.fluffy.color_scheme_seed', 0xFF5625BA),
   emojiSuggestionLocale<String>('emoji_suggestion_locale', ''),
-  enableSoftLogout<bool>('chat.fluffy.enable_soft_logout', false);
+  enableSoftLogout<bool>('chat.fluffy.enable_soft_logout', false),
+  autoSsoRedirect<bool>('chat.fluffy.auto_sso_redirect', false);
 
   final String key;
   final T defaultValue;
diff --git a/lib/pages/sign_in/sign_in_page.dart b/lib/pages/sign_in/sign_in_page.dart
index 8dd4390a2..354491a16 100644
--- a/lib/pages/sign_in/sign_in_page.dart
+++ b/lib/pages/sign_in/sign_in_page.dart
@@ -22,6 +22,7 @@ class SignInPage extends StatelessWidget {
     final theme = Theme.of(context);
     return ViewModelBuilder(
       create: () => SignInViewModel(Matrix.of(context), signUp: signUp),
+      onCreated: (context, viewModel) => viewModel.autoSsoIfEnabled(context),
       builder: (context, viewModel, _) {
         final state = viewModel.value;
         final publicHomeservers = state.filteredPublicHomeservers;
diff --git a/lib/pages/sign_in/view_model/sign_in_view_model.dart b/lib/pages/sign_in/view_model/sign_in_view_model.dart
index 55ff005c1..d03159c95 100644
--- a/lib/pages/sign_in/view_model/sign_in_view_model.dart
+++ b/lib/pages/sign_in/view_model/sign_in_view_model.dart
@@ -1,15 +1,19 @@
 import 'dart:convert';
 
-import 'package:flutter/widgets.dart';
+import 'package:flutter/foundation.dart';
+import 'package:flutter/material.dart';
 
 import 'package:collection/collection.dart';
-import 'package:matrix/matrix_api_lite/utils/logs.dart';
+import 'package:matrix/matrix.dart';
+import 'package:universal_html/html.dart' as html;
 
 import 'package:fluffychat/config/app_config.dart';
 import 'package:fluffychat/config/setting_keys.dart';
 import 'package:fluffychat/pages/sign_in/view_model/flows/sort_homeservers.dart';
 import 'package:fluffychat/pages/sign_in/view_model/model/public_homeserver_data.dart';
 import 'package:fluffychat/pages/sign_in/view_model/sign_in_state.dart';
+import 'package:fluffychat/utils/localized_exception_extension.dart';
+import 'package:fluffychat/utils/platform_infos.dart';
 import 'package:fluffychat/widgets/matrix.dart';
 
 class SignInViewModel extends ValueNotifier<SignInState> {
@@ -109,4 +113,70 @@ class SignInViewModel extends ValueNotifier<SignInState> {
   void setLoginLoading(AsyncSnapshot<bool> loginLoading) {
     value = value.copyWith(loginLoading: loginLoading);
   }
+
+  void autoSsoIfEnabled(BuildContext context) async {
+    if (!kIsWeb || signUp) return;
+    if (!AppSettings.autoSsoRedirect.value) return;
+    final defaultHS = AppSettings.defaultHomeserver.value;
+    if (defaultHS.isEmpty ||
+        defaultHS == AppSettings.defaultHomeserver.defaultValue) {
+      Logs().w(
+        '[AutoSSO] autoSsoRedirect requires defaultHomeserver to be set',
+      );
+      return;
+    }
+
+    setLoginLoading(AsyncSnapshot.waiting());
+    try {
+      var homeserver = Uri.parse(defaultHS);
+      if (homeserver.scheme.isEmpty) {
+        homeserver = Uri.https(defaultHS, '');
+      }
+      final client = await matrixService.getLoginClient();
+      final (_, _, loginFlows, _) = await client.checkHomeserver(homeserver);
+
+      // Check localStorage for a pending SSO token from a previous redirect.
+      final pendingResult = html.window.localStorage['flutter-web-auth-2'];
+      if (pendingResult != null && pendingResult.isNotEmpty) {
+        html.window.localStorage.remove('flutter-web-auth-2');
+        final token = Uri.parse(pendingResult).queryParameters['loginToken'];
+        if (token != null && token.isNotEmpty) {
+          await client.login(
+            LoginType.mLoginToken,
+            token: token,
+            initialDeviceDisplayName: PlatformInfos.clientName,
+          );
+          setLoginLoading(AsyncSnapshot.withData(ConnectionState.done, true));
+          return;
+        }
+      }
+
+      // No pending token — verify SSO support and redirect.
+      if (!loginFlows.any((flow) => flow.type == 'm.login.sso')) {
+        Logs().w('[AutoSSO] Homeserver does not support SSO');
+        setLoginLoading(AsyncSnapshot.withData(ConnectionState.done, false));
+        return;
+      }
+
+      final redirectUrl = Uri.parse(
+        html.window.location.href,
+      ).resolveUri(Uri(pathSegments: ['auth.html'])).toString();
+      final ssoUrl = client.homeserver!.replace(
+        path: '/_matrix/client/v3/login/sso/redirect',
+        queryParameters: {'redirectUrl': redirectUrl, 'action': 'login'},
+      );
+      html.window.location.href = ssoUrl.toString();
+    } catch (e, s) {
+      Logs().w('[AutoSSO] Failed', e, s);
+      setLoginLoading(AsyncSnapshot.withError(ConnectionState.done, e, s));
+      if (!context.mounted) return;
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(
+          content: Text(
+            e.toLocalizedString(context, ExceptionContext.checkHomeserver),
+          ),
+        ),
+      );
+    }
+  }
 }
diff --git a/lib/widgets/view_model_builder.dart b/lib/widgets/view_model_builder.dart
index 11c30b6e5..4cd992b78 100644
--- a/lib/widgets/view_model_builder.dart
+++ b/lib/widgets/view_model_builder.dart
@@ -5,11 +5,13 @@ class ViewModelBuilder<T extends ValueNotifier> extends StatefulWidget {
   final Widget Function(BuildContext context, T viewModel, Widget? child)
   builder;
   final Widget? child;
+  final void Function(BuildContext context, T viewModel)? onCreated;
   const ViewModelBuilder({
     super.key,
     required this.create,
     required this.builder,
     this.child,
+    this.onCreated,
   });
 
   @override
@@ -23,6 +25,12 @@ class _ViewModelBuilderState<T extends ValueNotifier>
   @override
   void initState() {
     _viewModel = widget.create();
+    if (widget.onCreated != null) {
+      WidgetsBinding.instance.addPostFrameCallback((_) {
+        if (!mounted) return;
+        widget.onCreated!(context, _viewModel);
+      });
+    }
     super.initState();
   }
 
diff --git a/web/auth.html b/web/auth.html
index 806485b73..9e380e9ee 100644
--- a/web/auth.html
+++ b/web/auth.html
@@ -2,12 +2,14 @@
 <title>Authentication complete</title>
 <p>Authentication is complete. If this does not happen automatically, please close the window.</p>
 <script>
+  var key = 'flutter-web-auth-2';
   if (window.opener) {
     window.opener.postMessage({
-      'flutter-web-auth-2': window.location.href
+      [key]: window.location.href
     }, window.location.origin);
+    window.close();
   } else {
-    localStorage.setItem('flutter-web-auth-2', window.location.href);
+    localStorage.setItem(key, window.location.href);
+    window.location.replace('/');
   }
-  window.close();
 </script>
\ No newline at end of file