3D Secure

3D Secure (3DS) (Three-Domain Secure) is an authentication protocol designed to reduce fraud in online credit and debit card transactions. It brands include Verified by Visa and Mastercard Identity Check.

If a transaction is deemed high-risk or if SCA is mandated, 3DS prompts the cardholder to verify their identity with the issuer (often via an SMS OTP or biometric app approval) before authorization proceeds. Successful 3DS authentication shifts the liability for chargebacks from the merchant to the issuer.