SCA

The PSD2 requirement that European card-not-present transactions be authenticated using two of three factors: knowledge (password), possession (device), or inherence (biometric). 3DS 2.0 is the default mechanism. Specific exemptions apply (low-value, MIT, secure corporate, transaction risk analysis).

In practice.

SCA is the two-factor authentication requirement behind European 3DS prompts. The practical merchant discipline is exemption management: low-risk exemptions, correctly chained MIT flags for renewals, and clean data that earns frictionless treatment. Poor SCA handling shows up directly as soft declines from European issuers.

Related terms: PSD2 · 3DS 2.0 · Frictionless flow