Payments glossary

25 terms merchants run into when choosing a payment provider.

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3D Secure (3DS)Security
An authentication protocol used by card schemes (Verified by Visa, Mastercard SecureCode) to provide additional security for card-not-present transactions, shifting fraud liability to the issuer.

A

Acquiring / AcquirerCore
The bank or financial institution that processes card transactions on behalf of a merchant. The acquirer settles funds to the merchant after deducting fees.
Acquiring BankCore
The financial institution that holds the merchant's account and processes card transactions. Often distinct from the payment gateway or PSP layer.
AMLCompliance
Anti-Money Laundering. A set of laws, regulations, and procedures intended to prevent criminals from disguising illegally obtained funds as legitimate income.

B

BNPLMethods
Buy Now Pay Later. A short-term credit product that allows consumers to split purchases into instalments, often interest-free. Providers include Klarna, Afterpay, and Affirm.

C

ChargebackRisk
A forced reversal of a transaction initiated by the cardholder's bank, typically due to dispute or fraud. Results in the funds being returned to the cardholder and a chargeback fee levied on the merchant.

E

EMVStandards
Europay, Mastercard, and Visa. The global standard for chip-based payment cards. EMV chips generate a unique transaction code for each payment, making card-present fraud significantly harder.

H

High-Risk MerchantRisk
A merchant categorised as higher risk by acquirers due to industry type (gambling, adult, pharmaceuticals), high chargeback rates, or cross-border volume. Often faces higher fees and stricter terms.

I

InterchangeFees
The fee paid by the acquiring bank to the issuing bank for each card transaction. Set by the card schemes (Visa, Mastercard) and forms the largest component of the MDR.
ISO (Independent Sales Organisation)Core
A third party authorised by card schemes to sell merchant accounts and payment services on behalf of an acquiring bank. ISOs earn a share of the processing revenue.
Issuer / Issuing BankCore
The bank or financial institution that issues payment cards to consumers. The issuer approves or declines transactions and holds the cardholder relationship.

K

KYCCompliance
Know Your Customer. Regulatory process of verifying the identity of customers/merchants before providing financial services. Required by AML regulations globally.

M

MDRFees
Merchant Discount Rate. The fee a merchant pays to accept card payments, usually expressed as a percentage of the transaction value. Includes interchange, scheme fees, and the acquirer margin.

O

Open BankingMethods
A system where banks share customer financial data (with consent) via APIs, enabling third-party apps to initiate payments or access account information directly without card networks.

P

Payment GatewayCore
Technology that captures and transmits payment data from the merchant to the acquirer. Can be hosted, redirect-based, or API-integrated.
PCI DSSCompliance
Payment Card Industry Data Security Standard. A set of security requirements for any entity that stores, processes, or transmits cardholder data. Maintained by the PCI Security Standards Council.
POSCore
Point of Sale. The location and system where in-person transactions occur. A POS system includes the hardware (terminal) and software that processes payments at retail.
PSD2Compliance
Payment Services Directive 2. An EU regulation governing electronic payment services, introducing open banking obligations and Strong Customer Authentication (SCA) requirements.
PSPCore
Payment Service Provider. A company that facilitates electronic transactions between merchants and customers, handling card acquiring, settlement, and often fraud prevention.

R

Rolling ReserveRisk
A percentage of a merchant's processed volume held by the acquirer as a security buffer against chargebacks and fraud. Released on a rolling basis (e.g., 10% held for 180 days).

S

SCACompliance
Strong Customer Authentication. A regulatory requirement under PSD2 in Europe requiring at least two independent authentication factors (something you know, have, or are) for electronic payments.
Scheme FeeFees
Fees charged by card networks (Visa, Mastercard, Amex) for transactions processed on their rails. Separate from interchange and typically passed through by acquirers.
SettlementOperations
The process of transferring funds from the acquirer to the merchant's bank account after a transaction has been authorised and captured. Typically T+1 to T+3 business days.

T

TokenisationSecurity
Replacing sensitive card data (PAN) with a non-sensitive equivalent called a token. Tokens are useless if intercepted and reduce PCI DSS scope for merchants.

V

Virtual IBANMethods
A unique IBAN assigned to a specific merchant or end-customer to route incoming bank transfers. Enables automated reconciliation without manual matching.