Two-Factor Authentication

Two-factor authentication, also known as two-step verification or multi-factor authentication, is a security measure that protects cardholders from third-party fraud by requiring two forms of verification before a purchase can be made. Under two-factor authentication, cardholders must commonly supply a password along with a PIN, a one-time email, an SMS code, or an authenticator app-based code. Biometric data or hardware devices can also be used as second factors.

When implemented successfully, two-factor authentication can reduce the incidence of account takeover fraud, brute-force attacks, identity theft, phishing, and social engineering attacks.