Set up Microsoft Authenticator on a new phone

Do this before retiring the old phone — you need the old one to approve adding the new one.

1. On the new phone, install Microsoft Authenticator from the App Store / Play Store.
2. On a computer, go to aka.ms/mfasetup, sign in.
3. Click “Add sign-in method” → Authenticator app.
4. Follow the prompts — you’ll be asked to scan a QR code with the new phone’s Authenticator.
5. Test it by signing out and signing back in — approve on the new phone.
6. Once it works, go back to Security info, remove the old phone as a method.
7. Add a backup method (your mobile number) so you’re never stuck again.