Sanctions screening is the compliance control of checking customers, counterparties and transactions against government sanctions lists before and during payment processing. The best known is the US OFAC Specially Designated Nationals, or SDN, list, alongside the EU, UN and UK HMT consolidated lists. Screening runs at onboarding and then continuously against every payment.
Why it matters
Sanctions screening is not a soft flag like a fraud score. A confirmed match is a hard stop that blocks the payment and can trigger a reporting obligation. For high risk merchants it sits beside KYC and AML as a control the acquirer must see working before it will process, because sanctions liability flows up to the acquiring bank and its own regulator. Weak screening is also how otherwise clean businesses get pulled into transaction laundering investigations, when a sanctioned party moves money through their MID. Manual or missing screening is one of the fastest routes to termination, because no acquirer will carry the regulatory exposure of a merchant that cannot evidence it.