What a processor's markup
actually pays for

"Processing fees" gets talked about as if it's one number a processor sets. It isn't. Every card swipe splits into three payments to three different parties, and the processor you signed with only controls one of them — and it's usually the smallest one. Merchants who don't know the split negotiate the wrong thing: they push their processor for a lower rate on a component the processor can't actually move.

This is a plain accounting of where the money in your effective rate goes, what each layer is called, who sets it, and what the one negotiable piece — the markup — actually pays for.

The three layers, in order

Every card-present or card-not-present transaction that runs on Visa, Mastercard, Discover, or American Express rails splits into the same three components, regardless of which processor you use:

• Interchange. Paid to the bank that issued the customer's card. Set by the card networks on a published schedule, updated twice a year (Visa and Mastercard both refresh rates each April, with a smaller October update). Neither you nor your processor negotiates this number — it is identical whether you process through us, a competitor, or a large national chain, for the same card and transaction type.
• Network assessments. Paid directly to the card network itself — Visa or Mastercard, separate from interchange, which goes to the issuing bank. Visa's credit assessment runs about 0.14% of volume; Mastercard's runs roughly 0.1375% plus a small flat per-transaction fee. Also not negotiable, and also identical across processors for the same card type.
• Processor markup. What's left. Under interchange-plus pricing, it's the only line shown separately — commonly a fraction of a percent plus a per-transaction fee (e.g., interchange + 0.20%–0.35% + $0.10). Under flat-rate or tiered pricing, this layer is blended invisibly into a single headline number, which is exactly why those structures are harder to audit.

Interchange: the layer nobody negotiates

Interchange is the fee your processor collects on behalf of, and passes entirely to, the bank that issued your customer's card — Chase, Capital One, whoever's name is on the plastic. Visa and Mastercard don't collect it themselves; they set the rate, publish it, and the issuing bank keeps it. It funds the issuer's side of the transaction: fraud loss coverage, the rewards points on that card, cardholder statement credit, and the issuer's cost of extending credit in the case of a credit card.

The rate varies enormously by card type and how the transaction is run. A regulated debit card swiped in person is capped by federal law — currently $0.21 plus 0.05% of the transaction, plus a possible $0.01 fraud-prevention adjustment, under the Durbin Amendment's implementing rule, Regulation II. A premium rewards or commercial credit card run online can carry interchange several multiples higher, because none of the debit-network caps apply to credit. That's the entire logic behind why your card mix is the single biggest lever on your effective rate — you aren't negotiating interchange down, you're changing which interchange tier your transactions fall into.

One development worth flagging honestly: in August 2025, a federal district court in North Dakota ruled in litigation over Regulation II that the Federal Reserve had exceeded its authority in setting the current debit interchange cap, and vacated the standard. As of this writing that ruling is being litigated further and the practical debit-cap number in use has not changed — we're flagging it as a live legal development, not a settled change to your rate. Re-check before relying on any specific debit-cap figure.

Network assessments: the smallest, most consistent layer

Assessments are separate from interchange and go straight to Visa or Mastercard themselves as the toll for running the rails — the fraud-detection network, the authorization infrastructure, the dispute-resolution system. Visa's published credit assessment is about 0.14% of transaction volume; Mastercard's runs close to 0.1375% plus a small flat per-transaction charge (the "NABU" fee), and Mastercard's separate acquirer assessment rose from 0.087% to 0.09% effective July 2025. These are the most stable component of your effective rate year over year, and — like interchange — completely outside any processor's control or negotiation.

Two processors quoting different effective rates on identical card mix aren't quoting different interchange. They're quoting different markups.

The markup: the only layer that funds the processor

Everything the processor itself provides — as distinct from what the card networks and issuing banks provide — is funded entirely out of the markup. That includes:

• Underwriting and risk management. Reviewing your business before approval, monitoring for fraud patterns, managing chargeback exposure across the whole merchant portfolio.
• PCI-scope infrastructure. Maintaining the tokenization, encryption, and compliance systems that keep card data out of your hands and off your servers.
• Dispute and chargeback handling. Staff and systems that manage representment, evidence submission, and network compliance monitoring.
• Gateway and terminal software. The actual point-of-sale software, online checkout integration, and reporting dashboard you use every day.
• Sales, onboarding, and support. Account setup, terminal provisioning, and whoever answers the phone when a transaction fails to settle.
• The processor's own margin. What's actually left after the above — the number that varies most between one processor and the next.

This is also why interchange-plus pricing is the only structure that lets you see this layer at all. A flat-rate quote of, say, 2.9% + $0.30 bundles all three layers into one number with no way to tell whether the markup inside it is 20 basis points or 90. Two flat-rate processors can quote the same headline rate on paper while one is keeping four times the markup of the other, simply because interchange happened to run lower on that merchant's card mix that month, leaving more room inside the flat number.

Why this matters when you're comparing quotes

The practical use of this breakdown is simple: when two processors quote different effective rates on the same business, on the same card mix, the difference is never interchange or assessments — those are fixed by the networks and identical everywhere. The difference is entirely inside the markup. That reframes the negotiation. Asking a processor to "lower my rate" without specifying the markup line is asking them to discount something they don't set two-thirds of. Asking specifically for the interchange-plus markup to be reduced — the basis points and the per-transaction cents — is asking for the one thing they actually control. See our rate review checklist for the exact language to use.

It also explains a pattern many merchants notice without understanding: your effective rate can rise even when your processor's rate card never changes. If your card mix shifts toward more rewards or commercial cards, interchange rises — and the processor's markup, sitting on top, stays exactly where it was. The processor didn't raise anything. The mix moved.

Frequently asked questions

What is a processor's markup in credit card processing?

The markup is the portion of your effective rate that the payment processor or ISO actually keeps, after interchange (paid to the card-issuing bank) and network assessments (paid to Visa/Mastercard) are passed through. Under interchange-plus pricing it's shown as a separate line — commonly a fraction of a percent plus a few cents per transaction. Under flat-rate and tiered pricing, the markup is blended into the headline rate and never itemized.

Is most of my processing rate interchange or markup?

For the large majority of merchants, interchange is the biggest single component of an effective rate — commonly 70–85% of what a merchant pays on a typical credit-card transaction, with network assessments and processor markup splitting the remainder. The exact split depends heavily on card mix: rewards and commercial cards carry materially higher interchange than a regulated debit card.

What does the processor's markup actually pay for?

It funds everything the processor itself does that the card networks and issuing banks don't: underwriting and risk management, PCI-scope infrastructure, chargeback and dispute handling, customer support, gateway and terminal software, sales and onboarding, and the processor's own margin. None of it goes to Visa, Mastercard, or the cardholder's bank — that money is already accounted for in interchange and assessments.

Can a merchant negotiate interchange rates?

No. Interchange rates are set by the card networks (Visa, Mastercard, Discover, American Express) and published on a fixed schedule, typically updated each April and October. Neither the merchant nor the processor can negotiate interchange — it passes through unchanged regardless of who processes the transaction. The only genuinely negotiable layer is the processor's markup.

Why do two processors quote different effective rates on the same card mix?

Because interchange and assessments are identical for both quotes — the only variable is markup. A lower quoted effective rate on the same card mix means a smaller markup, a bundled/blended structure that hides the split, or in rare cases a processor absorbing volume-based network rebates. Comparing two interchange-plus quotes side by side isolates the real difference: the markup line.