Authentication in Expo Router

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How to implement authentication and protect routes with Expo Router.

Note: This guide requires SDK 53. For the previous version of this guide see Authentication (redirects).

With Expo Router, all routes are always defined and accessible. You can use runtime logic to redirect users away from specific screens depending on whether they are authenticated. There are two different techniques for authenticating users within routes. This guide provides an example that demonstrates the functionality of standard native apps.

Using Protected Routes

Protected routes allow you to prevent users from accessing certain routes using client-side navigation. If a user tries to navigate to a protected screen, or if a screen becomes protected while it is active, they will be redirected to the anchor route (usually the index screen) or the first available screen in the stack. Consider the following project structure that has a /sign-in route that is always accessible and a (app) group that requires authentication:

app

_layout.tsxControls what is protected

sign-in.tsxAlways accessible

(app)

_layout.tsxRequires authorization

index.tsxShould be protected by the (app)/_layout

To follow the above example, set up a React Context provider that can expose an authentication session to the entire app. You can implement your custom authentication session provider or use the one from the Example authentication context below.

Example authentication context

This provider uses a mock implementation. You can replace it with your own authentication provider.

ctx.tsx

import { use, createContext, type PropsWithChildren } from 'react';

import { useStorageState } from './useStorageState';

const AuthContext = createContext<{
  signIn: () => void;
  signOut: () => void;
  session?: string | null;
  isLoading: boolean;
}>({
  signIn: () => null,
  signOut: () => null,
  session: null,
  isLoading: false,
});

// Use this hook to access the user info.
export function useSession() {
  const value = use(AuthContext);
  if (!value) {
    throw new Error('useSession must be wrapped in a <SessionProvider />');
  }

  return value;
}

export function SessionProvider({ children }: PropsWithChildren) {
  const [[isLoading, session], setSession] = useStorageState('session');

  return (
    <AuthContext
      value={{
        signIn: () => {
          // Perform sign-in logic here
          setSession('xxx');
        },
        signOut: () => {
          setSession(null);
        },
        session,
        isLoading,
      }}>
      {children}
    </AuthContext>
  );
}

The following code snippet is a basic hook that persists tokens securely on native with expo-secure-store and in local storage on web.

useStorageState.ts

import  { useEffect, useCallback, useReducer } from 'react';
import * as SecureStore from 'expo-secure-store';
import { Platform } from 'react-native';

type UseStateHook<T> = [[boolean, T | null], (value: T | null) => void];

function useAsyncState<T>(
  initialValue: [boolean, T | null] = [true, null],
): UseStateHook<T> {
  return useReducer(
    (state: [boolean, T | null], action: T | null = null): [boolean, T | null] => [false, action],
    initialValue
  ) as UseStateHook<T>;
}

export async function setStorageItemAsync(key: string, value: string | null) {
  if (Platform.OS === 'web') {
    try {
      if (value === null) {
        localStorage.removeItem(key);
      } else {
        localStorage.setItem(key, value);
      }
    } catch (e) {
      console.error('Local storage is unavailable:', e);
    }
  } else {
    if (value == null) {
      await SecureStore.deleteItemAsync(key);
    } else {
      await SecureStore.setItemAsync(key, value);
    }
  }
}

export function useStorageState(key: string): UseStateHook<string> {
  // Public
  const [state, setState] = useAsyncState<string>();

  // Get
  useEffect(() => {
    if (Platform.OS === 'web') {
      try {
        if (typeof localStorage !== 'undefined') {
          setState(localStorage.getItem(key));
        }
      } catch (e) {
        console.error('Local storage is unavailable:', e);
      }
    } else {
      SecureStore.getItemAsync(key).then(value => {
        setState(value);
      });
    }
  }, [key]);

  // Set
  const setValue = useCallback(
    (value: string | null) => {
      setState(value);
      setStorageItemAsync(key, value);
    },
    [key]
  );

  return [state, setValue];
}

Create a SplashScreenController to manage the splash screen. Authentication loading is asynchronous, so keep the splash screen visible until authentication loads.

splash.tsx

import { SplashScreen } from 'expo-router';
import { useSession } from './ctx';

export function SplashScreenController() {
  const { isLoading } = useSession();

  if (!isLoading) {
    SplashScreen.hideAsync();
  }

  return null;
}

Add the SessionProvider to your root layout. This gives your entire app access to the authentication context. Ensure the SplashScreenController is inside the SessionProvider.

app/_layout.tsx

import { Stack } from 'expo-router';

import { SessionProvider } from '../ctx';
import { SplashScreenController } from '../splash';

export default function Root() {
  // Set up the auth context and render your layout inside of it.
  return (
    <SessionProvider>
      <SplashScreenController />
      <RootNavigator />
    </SessionProvider>
  );
}

// Create a new component that can access the SessionProvider context later.
function RootNavigator() {
  return <Stack />;
}

Create the /sign-in screen. This screen toggles authentication using signIn(). Since this screen is outside the (app) group, the group's layout and authentication check do not run when rendering this screen. This lets logged-out users access this screen.

app/sign-in.tsx

import { router } from 'expo-router';
import { Text, View } from 'react-native';

import { useSession } from '../ctx';

export default function SignIn() {
  const { signIn } = useSession();
  return (
    <View style={{ flex: 1, justifyContent: 'center', alignItems: 'center' }}>
      <Text
        onPress={() => {
          signIn();
          // Navigate after signing in. You may want to tweak this to ensure sign-in is successful before navigating.
          router.replace('/');
        }}>
        Sign In
      </Text>
    </View>
  );
}

Now modify the RootNavigator to protect routes based on your SessionProvider.

app/_layout.tsx

// All import statements remain the same except you need to import `useSession` from your `ctx.tsx` file.
import { SessionProvider } from '../ctx';

// All of the above code remains unchanged. Update the `RootNavigator` to protect routes based on your `SessionProvider` below.

function RootNavigator() {
  const { session } = useSession();

  return (
    <Stack>
      <Stack.Protected guard={!!session}>
        <Stack.Screen name="(app)" />
      </Stack.Protected>

      <Stack.Protected guard={!session}>
        <Stack.Screen name="sign-in" />
      </Stack.Protected>
    </Stack>
  );
}

Implement an authenticated screen that lets users sign out.

app/(app)/index.tsx

import { Text, View } from 'react-native';

import { useSession } from '../../ctx';

export default function Index() {
  const { signOut } = useSession();
  return (
    <View style={{ flex: 1, justifyContent: 'center', alignItems: 'center' }}>
      <Text
        onPress={() => {
          // The `app/(app)/_layout.tsx` redirects to the sign-in screen.
          signOut();
        }}>
        Sign Out
      </Text>
    </View>
  );
}

Create the app/(app)/_layout.tsx:

app/(app)/_layout.tsx

import { Stack } from 'expo-router';

export default function AppLayout() {
  // This renders the navigation stack for all authenticated app routes.
  return <Stack />;
}

You now have an app that will present the splash screen until the initial authentication state has loaded and will redirects to the sign-in screen if the user is not authenticated. If a user visits a deep link to any routes with the authentication check, they'll be redirected to the sign-in screen.

Modals and per-route authentication

Another common pattern is to render a sign-in modal over the top of the app. This enables you to dismiss and partially preserve deep links when the authentication is complete. However, this pattern requires routes to be rendered in the background as these routes require handling data loading without authentication.

app

_layout.tsxDeclares global session context

(app)

_layout.tsx

sign-in.tsxModal presented over the root

(root)

_layout.tsxProtects child routes

index.tsxRequires authorization

app/(app)/_layout.tsx

import { Stack } from 'expo-router';

export const unstable_settings = {
  initialRouteName: '(root)',
};

export default function AppLayout() {
  return (
    <Stack>
      <Stack.Screen name="(root)" />
      <Stack.Screen
        name="sign-in"
        options={{
          presentation: 'modal',
        }}
      />
    </Stack>
  );
}

More information

For more information, read the Protected routes documentation to learn more about patterns.

How to use Protected Routes in Expo Router V5 and higher for smooth authentication

Learn how to use Protected Routes in Expo Router V5 and higher to create an authentication flow.

Middleware

Traditionally, websites may leverage some form of server-side redirection to protect routes. Expo Router on the web currently only supports build-time static generation and has no support for custom middleware or serving. This can be added in the future to provide a more optimal web experience. In the meantime, authentication can be implemented by using client-side redirects and a loading state.