# How to change Authentication strategy | Next.js Firebase SaaS Kit

> Learn how to change the authentication strategy in Makerkit. Choose between email and password, phone number, email link, and OAuth.

*Canonical: https://makerkit.dev/docs/next-fire/how-to/authentication/change-auth-strategy*

---

Makerkit supports various authentication strategies supported by Firebase. We can customize these using the global configuration at `src/configurationt.ts`.

In the configuration file, you can find the following code:

```ts
auth: {
  // Enable MFA. You must upgrade to GCP Identity Platform to use it.
  // see: https://cloud.google.com/identity-platform/docs/product-comparison
  enableMultiFactorAuth: true,
  // When enabled, users will be required to verify their email address
  // before being able to access the app
  requireEmailVerification:
    process.env.NEXT_PUBLIC_REQUIRE_EMAIL_VERIFICATION === 'true',
  // NB: Enable the providers below in the Firebase Console
  // in your production project
  providers: {
    emailPassword: true,
    phoneNumber: false,
    emailLink: false,
    oAuth: [GoogleAuthProvider],
  },
},
```

We will need to edit this file to change the authentication strategy.

### Enabling Email and Password Authentication

This is the default authentication strategy. It allows users to sign up and sign in using their email and password.

To enable this strategy, set `providers.emailPassword` to `true`.

```tsx
providers: {
  emailPassword: false,
  phoneNumber: true,
  emailLink: false,
  oAuth: [GoogleAuthProvider],
},
```

### Enabling Phone Number Authentication

This strategy allows users to sign up and sign in using their phone number.

To enable this strategy, set `providers.phoneNumber` to `true`.

```tsx
providers: {
  emailPassword: false,
  phoneNumber: true,
  emailLink: false,
  oAuth: [GoogleAuthProvider],
},
```

### Enabling Email Link Authentication

This strategy allows users to sign up and sign in using their email address. A link will be sent to their email address to verify their identity.

To enable this strategy, set `providers.emailLink` to `true`.

```tsx
providers: {
  emailPassword: false,
  phoneNumber: trfalseue,
  emailLink: true,
  oAuth: [GoogleAuthProvider],
},
```

### Enabling OAuth Authentication

This strategy allows users to sign up and sign in using their social media accounts. You can enable multiple OAuth providers.

To enable this strategy, set `providers.oAuth` to an array of OAuth providers.

```tsx
import { GoogleAuthProvider, FacebookAuthProvider } from 'firebase/auth';

providers: {
  emailPassword: false,
  phoneNumber: false,
  emailLink: false,
  oAuth: [GoogleAuthProvider, FacebookAuthProvider],
},
```

## Can I use multiple authentication strategies?

Yes, you can use multiple authentication strategies. For example, you can enable email and password authentication and phone number authentication at the same time.

```tsx
providers: {
  emailPassword: true,
  phoneNumber: true,
  emailLink: false,
  oAuth: [GoogleAuthProvider],
},
```

With that said, the UI is not designed to support multiple authentication strategies. *You will need to customize the UI to support multiple authentication strategies**.