Accepting digital payments usually involves several parties: a merchant, a payment gateway or processor, an acquiring institution, a card network or payment rail, and the customer's bank or wallet provider. The pricing model determines how those costs appear on a merchant's bill.

Common pricing components

• Interchange: In card payments, an amount associated with the transfer between acquiring and issuing institutions, subject to applicable rules and regulation.
• Network or scheme fees: Charges associated with use of a card network or payment scheme.
• Processor or gateway fees: Charges for processing, routing, tokenization, reporting, or related services.
• Acquiring fees: Charges under the merchant's acquiring agreement.
• Cross-border and currency fees: May apply when issuer, merchant, or settlement currencies differ.
• Fixed transaction fees: A per-transaction charge in addition to a percentage.
• Additional charges: Chargebacks, refunds, monthly minimums, hardware, PCI-related services, fraud tools, or payouts may be billed separately.

Not every provider itemizes the same way. Pricing also varies by country, card type, sales channel, transaction volume, and contract.

Flat-rate versus interchange-plus

A flat-rate model bundles multiple costs into a simple published rate. Interchange-plus pricing typically separates interchange from a provider markup and some other charges. Neither is automatically best for every merchant. Compare actual statements and effective cost across a representative transaction mix.

How to calculate effective processing cost

Divide all payment-related fees for a period by the total processed payment volume for the same period. Include fixed fees and ancillary charges, and document what is included. Compare providers using the same period, currencies, card mix, and transaction channels.

Questions to ask providers

1. What is included in the headline rate?
2. Are international cards priced differently?
3. Are refunds and chargebacks charged separately?
4. What are payout timing and payout fees?
5. Are there monthly minimums or termination fees?
6. Can rates change, and how much notice is provided?
7. How are disputes and fraud tools priced?

Bottom line

The cheapest-looking headline rate may not yield the lowest total cost. Use real transaction data, review the full contract, and compare all fees that affect the merchant's net proceeds.

Sources and further reading

• UK Payment Systems Regulator: Ways of paying
• European Commission: Single Euro Payments Area (SEPA)

This article is educational. Merchant contracts, fee structures, and applicable regulations vary by provider and jurisdiction.