What is multi-factor authentication?

Multi-factor authentication (MFA) is when you use two or more different methods or ‘factors’, such as a password and a code, to verify your identity when accessing an online account.

It’s a security measure that helps to protect your online accounts by making it harder for unauthorised people to gain access.

MFA is sometimes called two-factor authentication (2FA) or two-step verification.

Page last updated 27 October 2025