Free tools
Payments glossary
The Gray Merchants payments glossary is a plain-English reference for the terms merchants meet across underwriting, credit card processing, chargeback management, and high-risk merchant accounts. It covers how a card issued by a bank actually gets a transaction approved, what an electronic funds transfer (EFT) is and how it differs from a card network payment, and the fee and dispute vocabulary that shows up on your statement. Search 93 definitions covering rolling reserves, ACH processing, and interchange, in the same language we use when we talk to you. Most entries link through to a full guide.
- 3D SecureSecurity & Authentication
- An authentication protocol that verifies the cardholder before authorization, reducing fraud liability and meeting PSD2 SCA requirements. Read more
- Account Takeover (ATO)Fraud & Risk
- Fraud that occurs when attackers gain access to customer accounts and use stored payment credentials for unauthorized transactions.
- Account UpdaterPayment Methods & Rails
- A card network service that refreshes stored card details when a customer's card is reissued, reducing failed recurring charges. Read more
- ACH ReturnPayment Methods & Rails
- An ACH entry sent back unpaid, for insufficient funds, a closed account, or a customer's claim it was unauthorized. Returns run under banking rules with different windows than card chargebacks. Read more
- ACH TransferPayment Methods & Rails
- Bank-to-bank payments processed via the Automated Clearing House network, typically in the US. Read more
- Acquirer (Acquiring Bank)Ecosystem & Participants
- The licensed bank or financial institution that holds the merchant account and assumes liability for card transactions. Read more
- Acquirer Reference Number (ARN)Disputes & Chargebacks
- A unique 23-digit transaction identifier used to trace card payments for dispute resolution and refund tracking.
- Acquiring AgreementLegal & Compliance
- The contract between a merchant and an acquirer defining pricing structure, settlement terms, rolling reserves, and liability guidelines.
- Address Verification Service (AVS)Fraud & Risk
- A system that compares a cardholder's billing address against issuer records to detect potential fraud. Read more
- AggregatorEcosystem & Participants
- A provider that pools many small merchants under one merchant account. Fast to join and easy to be removed from, because you never held the bank relationship. Read more
- Anti-Money Laundering (AML)Regulatory Framework
- Strict obligations to detect, prevent, and report money laundering through transaction monitoring and Customer Due Diligence (CDD).
- API GatewayTechnical Infrastructure
- Provides direct connection between a merchant's application checkout and the central payments engine managed by Gray Merchants.
- ArbitrationDisputes & Chargebacks
- The final stage of a dispute, decided by the card network for a fee. Both the fee and the outcome fall on the losing side.
- AuthorizationTransaction Flow
- The process of verifying that a card is active and has sufficient funds or credit to cover a transaction.
- Authorization HoldTransaction Flow
- A temporary reduction of a cardholder's available credit while a transaction is pending. It isn't a charge, and it drops off if the merchant never captures it.
- Bank Secrecy Act (BSA)Regulatory Framework
- The US anti-money-laundering statute requiring financial institutions to keep records and report suspicious activity. It's the reason your acquirer asks who owns your business.
- Basis Point (bps)Fees & Pricing
- One hundredth of a percentage point. Processor markups and dispute thresholds are usually quoted in basis points, so 25 bps means 0.25%.
- BatchTransaction Flow
- A group of authorized transactions a merchant submits together, usually once a day, to be cleared and funded. Missing a batch cutoff pushes your deposit to the next business day.
- Batch Cutoff TimeTransaction Flow
- The daily deadline for submitting a batch to be funded on the next cycle. Sales captured after cutoff settle a day later, which is the usual reason a deposit appears late. Read more
- Beneficial OwnerUnderwriting
- Anyone owning or controlling a meaningful share of a business. Banks collect ownership details under their own due diligence rules, separately from any filing obligation. Read more
- BIN SponsorshipEcosystem & Participants
- When an institution uses the Bank Identification Number of a licensed bank to route and process transactions.
- CaptureTransaction Flow
- Converting an authorization into a charge that will actually be funded. Some businesses authorize at order time and capture at shipment, which matters for dispute timing.
- Card Not Present (CNP)Transaction Flow
- Transactions where the cardholder and the physical card are not present at the point of sale, such as e-commerce or phone orders. Read more
- Card Present (CP)Transaction Flow
- A transaction where the physical card is dipped, tapped, or swiped at a terminal. Card present sales carry lower interchange and lower fraud liability than keyed or online sales. Read more
- Card TestingFraud & Risk
- Attackers running small transactions against a site to find which stolen card numbers still work. Low-priced products and free trials are the usual targets. Read more
- Cardholder DataSecurity & Authentication
- The card number, cardholder name, expiration date, and service code. What PCI DSS exists to protect, and what you want never touching your own servers. Read more
- Cardholder Data Environment (CDE)Security & Authentication
- The people, processes, and technology that store, process, or transmit cardholder data or sensitive authentication data.
- Cash DiscountFees & Pricing
- Posting a higher list price and discounting it for cash payment. Structurally different from surcharging and treated differently under card network rules and state law. Read more
- ChargebackDisputes & Chargebacks
- A forced reversal of funds initiated by the cardholder's issuing bank, typically due to fraud, unrecognized charges, or non-delivery. Read more
- Chargeback AlertFraud & Risk
- A notification service that tells a merchant a dispute has been filed before it becomes a formal chargeback, leaving a window to refund instead. Read more
- Chargeback RatioDisputes & Chargebacks
- The percentage of a merchant's total transactions that result in chargebacks. Keeping this below 0.9% is critical for network compliance. Read more
- Chargeback ThresholdUnderwriting
- The dispute rate at which a processor or network escalates an account into monitoring or termination. Sitting just under one is not the same as being safe. Read more
- ClearingTransaction Flow
- The step after authorization where the acquirer sends the completed transaction to the card network, which passes it to the issuer for posting to the cardholder's account. Clearing is when the sale becomes a real debit, not just a hold.
- Compelling EvidenceDisputes & Chargebacks
- The documentation a card network accepts as proof a transaction was legitimate: delivery confirmation, signed agreements, usage logs, or prior undisputed purchases from the same cardholder. Read more
- Customer Due Diligence (CDD)Regulatory Framework
- The bank's obligation to identify and verify who it is doing business with, including beneficial owners. Refusing to provide it is a fast decline. Read more
- CVV / CVV2Security & Authentication
- The short verification code printed on a card but not stored in the magnetic stripe. Checking it helps prove the buyer physically had the card.
- Digital SkimmingFraud & Risk
- Malicious code injected into a checkout page to capture card details as they're typed. The merchant's own site becomes the collection point. Read more
- Discount RateFees & Pricing
- The fee percentage charged to the merchant for processing a credit or debit card transaction.
- Dispute Monitoring ProgramDisputes & Chargebacks
- A card network program that places merchants above a dispute threshold into enhanced monitoring, with fines and remediation requirements. Visa's threshold is a 0.9% dispute ratio combined with at least 100 disputes in a month. Read more
- Dual PricingFees & Pricing
- Displaying two prices, one for card and one for cash, so the customer sees both before choosing. Compliance depends on how the prices are disclosed at the point of sale. Read more
- Dynamic Currency Conversion (DCC)Fees & Pricing
- A service that offers customers the option to pay in their home currency rather than the merchant’s local currency at the point of sale.
- Early Termination Fee (ETF)Fees & Pricing
- A charge for closing a merchant account before the contract term ends. Worth finding in the agreement before you sign, not after you want to leave. Read more
- Effective RateFees & Pricing
- Total processing fees divided by total sales volume, times 100. It's the only number that lets you compare two providers fairly, because it captures monthly, statement, PCI, and batch fees that quoted rates leave out. Read more
- EMVSecurity & Authentication
- The chip card standard. Using a chip at a terminal shifts counterfeit fraud liability away from the merchant, which is why keyed and swiped fallbacks cost more. Read more
- First-Party FraudDisputes & Chargebacks
- A dispute filed by the genuine cardholder over a purchase they actually made and received. Also called friendly fraud, and it's the hardest category to prevent because the card was never stolen. Read more
- Flat Rate PricingFees & Pricing
- One blended percentage covering interchange, network assessments, and processor margin. Simple to predict, impossible to reconcile, because nothing is broken out. Read more
- Friendly FraudFraud & Risk
- When a consumer makes an online purchase with their own credit card, and then requests a chargeback from the issuing bank after receiving the goods or services, often claiming they didn't authorize the purchase. Read more
- High-Risk MerchantUnderwriting
- A business classified as having an elevated risk of chargebacks, fraud, or legal complications due to industry type or processing history. Read more
- Independent Sales Organization (ISO)Ecosystem & Participants
- A third-party company, like Gray Merchants, that brokers merchants and sets up payment processing services. Read more
- Interchange FeeFees & Pricing
- The base fee paid by the acquiring bank (and passed to the merchant) to the cardholder's issuing bank for each transaction processed. Read more
- Interchange PlusFees & Pricing
- A pricing model that shows the wholesale interchange cost and the processor's markup as separate line items. It's the only common model you can audit against the networks' published rate schedules. Read more
- Issuer (Issuing Bank)Ecosystem & Participants
- The financial institution that issues the credit or debit card to the consumer and assumes responsibility for the cardholder's debt. Read more
- KYC (Know Your Customer)Regulatory Framework
- The mandatory process of identifying and verifying the identity of clients when opening an account and periodically over time.
- Level 2 & Level 3 ProcessingEcosystem & Participants
- Additional data points (like tax amounts and line items) passed during a B2B or B2G transaction to secure lower interchange rates. Read more
- MATCH List (TMF)Fraud & Risk
- The Member Alert to Control High-Risk Merchants (MATCH) system, a blacklist barring merchants from obtaining new acquiring accounts. Read more
- Merchant AccountEcosystem & Participants
- A bank account that lets a business accept card payments, held with an acquiring bank that carries the risk if the business fails to deliver. Read more
- Merchant Category Code (MCC)Ecosystem & Participants
- The four-digit code classifying what a business sells. Your acquirer assigns it, not you, and it drives interchange, risk treatment, and sometimes whether a card will authorize at all. Read more
- Merchant ID (MID)Ecosystem & Participants
- The unique number identifying your business to the card networks and your acquirer. A dedicated MID in your own name is a different thing from processing under an aggregator's master MID. Read more
- Money Services Business (MSB)Regulatory Framework
- A FinCEN classification covering money transmitters and similar businesses, carrying registration and anti-money-laundering obligations.
- Monthly MinimumFees & Pricing
- A floor on processing fees. If your percentage-based fees fall below it in a given month, the processor bills the difference.
- MOTOTransaction Flow
- Mail order and telephone order transactions, where card details are taken by phone, post, or email and keyed in by staff. MOTO is treated as card not present for interchange and liability. Read more
- Multi-MID StructureEcosystem & Participants
- Running more than one merchant account so volume, risk, and downtime are spread rather than concentrated. You cannot build redundancy inside a single pooled account. Read more
- Network AssessmentFees & Pricing
- The fee Visa or Mastercard charges on each transaction for use of the network, separate from interchange. Like interchange, it isn't negotiable by the merchant or the processor.
- ODFIPayment Methods & Rails
- Originating Depository Financial Institution. The bank that submits an ACH entry into the network on behalf of the originator. Read more
- Payment Facilitator (PayFac)Ecosystem & Participants
- A designated entity that effectively acts as the master merchant account, sub-boarding smaller merchants underneath its umbrella. Read more
- Payment GatewayTechnical Infrastructure
- The technology that captures and transfers payment data from the customer to the acquirer and then transfers the payment acceptance or decline back. Read more
- PCI DSSSecurity & Authentication
- The Payment Card Industry Data Security Standard is a set of security standards designed to ensure all companies that maintain credit card information maintain a secure environment. Read more
- Pre-ArbitrationDisputes & Chargebacks
- The stage after representment where the issuer challenges the merchant's evidence again. Losing here usually costs more than the original transaction.
- ProcessorEcosystem & Participants
- The entity that executes the transaction by transmitting data between the merchant, acquiring bank, and the card networks. Read more
- RDFIPayment Methods & Rails
- Receiving Depository Financial Institution. The bank that receives an ACH entry and posts it to the customer's account. Read more
- Reason CodeDisputes & Chargebacks
- The network code identifying why a chargeback was filed. It determines what evidence you need and how long you have to respond. Read more
- Recurring BillingPayment Methods & Rails
- Charging a stored payment credential on a schedule. Subscription businesses live here, and so does a large share of first-party dispute volume. Read more
- Refund RatioDisputes & Chargebacks
- Refunds as a share of transactions or volume. Processors watch it alongside chargebacks, because a spike can signal fulfilment problems before disputes appear. Read more
- Refund vs VoidTransaction Flow
- A void cancels a transaction before it settles, whereas a refund reverses a transaction that has already been settled and funded.
- Regulation ERegulatory Framework
- The federal rule governing electronic fund transfers and consumer error resolution. It sets what a bank must do when a consumer reports an unauthorized transaction.
- Regulation IIRegulatory Framework
- The Federal Reserve rule capping debit interchange for issuers with $10 billion or more in assets, at $0.21 plus 0.05% of the transaction, plus a $0.01 fraud-prevention adjustment where eligible. Read more
- RepresentmentDisputes & Chargebacks
- The merchant's formal response to a chargeback, submitting evidence that the transaction was valid and the service or goods were delivered as agreed. Read more
- ReserveUnderwriting
- Funds an acquirer holds back to cover potential chargebacks. Comes in rolling, capped, and upfront forms, and the release schedule matters more than the percentage. Read more
- Retrieval RequestDisputes & Chargebacks
- An issuer's request for a copy of a transaction record before filing a chargeback. Answering one promptly sometimes stops a dispute from being filed at all.
- Rolling ReserveUnderwriting
- A risk management strategy where the acquirer holds a percentage of a merchant's daily processing volume for a set period to cover potential future chargebacks. Read more
- Same Day ACHPayment Methods & Rails
- An ACH option that settles the same business day rather than in one to three days. In 2025 it carried 1.4 billion payments worth $3.9 trillion, per Nacha. Read more
- Self-Assessment Questionnaire (SAQ)Security & Authentication
- The PCI DSS validation form a merchant completes. Which version applies depends on how you accept payments, and your acquirer tells you which one. Read more
- SettlementTransaction Flow
- The final stage of the payment process where funds are transferred from the cardholder's issuing bank to the merchant's acquiring bank account.
- Sub-MerchantEcosystem & Participants
- A business processing under a payment facilitator's master merchant account rather than holding its own. The facilitator, not the sub-merchant, holds the contract with the acquiring bank. Read more
- SurchargingFees & Pricing
- Adding a fee to a credit card transaction to pass processing cost to the customer. In the US it applies to credit only, requires 30 days' notice to your acquirer, and cannot exceed your cost of acceptance. Read more
- Third-Party Payment ProcessorEcosystem & Participants
- A company that processes payments on behalf of other businesses. US bank regulators treat these relationships as higher risk, especially where the bank has no direct relationship with the underlying merchant.
- Tiered PricingFees & Pricing
- A model that sorts transactions into qualified, mid-qualified, and non-qualified buckets at different rates. The processor defines the tiers, not the networks, so there is no published standard to check them against. Read more
- TokenizationSecurity & Authentication
- The process of replacing sensitive payment data with a unique, non-sensitive identifier (token) that cannot be reverse-engineered. Read more
- UnderwritingUnderwriting
- The process where a bank evaluates a merchant's business model, financials, and risk profile to determine acquiring approval and terms. Read more
- Velocity CheckFraud & Risk
- A rule limiting how many transactions or how much value a customer, card, or IP can push through in a set period. A standard first defense against card testing. Read more
- Virtual CardPayment Methods & Rails
- A card number issued for a single supplier, purchase order, or spending limit, then closed once it clears. Common in B2B procurement for spend control. Read more
- Virtual TerminalTechnical Infrastructure
- A web-based application that allows merchants to manually enter credit card transactions, typically used for MOTO (Mail Order/Telephone Order) businesses. Read more
- Volume CapUnderwriting
- The monthly processing limit set on your account at underwriting. Exceeding it without warning your processor is a common trigger for a hold.
Related tools & guides
Put these terms to work — look up a code with the MCC directory, read up on high-risk merchant accounts and chargeback defense, or run the numbers with our free calculators.