3D Secure

An authentication protocol that adds a second factor, typically a one-time code, biometric, or device check, to card-not-present transactions. Successful 3DS authentication shifts liability for fraud chargebacks from the merchant to the issuer. The current version is 3DS 2.0 (EMV 3DS), which supports frictionless authentication for low-risk transactions.

In practice.

For merchants, 3D Secure is mainly a liability and approval-rate lever. Running a transaction through 3DS shifts fraud chargeback liability to the issuer, which matters in verticals where fraud disputes dominate. The trade-off is checkout friction, so most merchants apply it selectively based on risk signals rather than on every transaction.

Related terms: 3DS 2.0 · SCA · PSD2 · Liability shift