Lesson 4 · Practitioner · Both · 14 min
Merchants, PSPs, Gateways & Acquirers
Unpack the merchant acceptance stack — card present vs card not present at a high level, and how merchants, gateways, PSPs, and acquirers divide responsibility.
Objectives
- ▸Explain CP vs CNP risk and data flows at a high level
- ▸Differentiate gateway, PSP, and acquirer roles
- ▸Map money movement from customer to merchant bank account
- ▸Identify what a merchant actually contracts for (acceptance + payout + risk)
Card present (CP / POS / tap-to-pay) captures the credential in a controlled terminal environment with EMV cryptograms — lower fraud rates, different scheme fee and chargeback reasons. Card not present (CNP: ecom, MOTO, stored credential) relies on PAN/token entry, AVS/CVV where used, and often 3-D Secure. Product teams should not copy CP UX patterns onto CNP risk engines.
- CP: terminal, offline floor limits rare in modern EMV online auth
- CNP: browser/app SDK, redirects, or native auth; higher fraud and friendly fraud
- Omnichannel merchants need unified order IDs across both
Key terms
Card presentCard not presentAcquirerPayment gatewayPSPMCCMerchant of recordSettlementMDR