Where the margin hides: dissecting the payments and lending value chain

You tap your card for a 4 dollar coffee. The merchant receives roughly 3.90. That missing 10 cents or so, around 2 to 3 percent, is one of the most contested revenue streams in modern banking. Four different companies just split it in the time it took the terminal to beep.

This lesson follows that dime. Understanding who grabs what, and who is stuck being a low-margin utility, tells you almost everything about power in payments.

The four roles behind one tap

Every card payment involves four functions. Sometimes one company plays several, but the roles are distinct.

• Issuer: the bank that gave the cardholder their card (Chase, Bank of America, Barclays, Revolut). It carries the credit risk and funds the transaction.
• Acquirer: the bank or firm that signs up the merchant and deposits the funds into the merchant's account (Worldpay, Fiserv, Adyen).
• Card network (also called the scheme): Visa or Mastercard in most of the world, American Express in a narrower niche. It runs the rails that route the authorization and set the rules.
• Processor: the technical plumbing that moves the message from terminal to network and back. Often bundled with the acquirer (Stripe, Adyen, Fiserv), sometimes standalone.

Keep those four straight and the money flow becomes readable.

Splitting the 2 percent

Let us use a concrete example. Assume a 100 dollar purchase on a US consumer credit card, with a Merchant Discount Rate (MDR, the total fee the merchant pays) of about 2.5 percent, so 2.50 dollars total. These are illustrative but realistic figures; actual rates vary by card type, merchant size and region.

Here is roughly how that 2.50 divides. Numbers are estimates for a typical US credit card transaction as of 2026.

Interchange is the fee the acquirer pays the issuer, set by the network but paid to the bank that issued the card. It is the largest slice, and the issuer keeps it. This is why banks fight so hard to get their card into your wallet: every swipe pays them.

Scheme fees (also called assessments) go to Visa or Mastercard. Small per transaction, but they take it on nearly every card payment on Earth.

The acquirer and processor split what remains. For a big merchant with negotiating power, that markup is razor thin. For a small cafe on a flat-rate plan, the acquirer keeps more.

For a deeper reference on how interchange is structured in the US, the Federal Reserve publishes data on debit card interchange under Regulation II: Federal Reserve regulated interchange data.

Who has power, and who is a utility

Now the interesting part. Same four players, wildly different margins.

The networks: the toll booth

Visa and Mastercard are the highest-margin businesses in the entire chain. They own the rails, set the rules, and take a small cut of enormous volume. They carry no credit risk and hold no deposits. Their operating margins are among the highest of any large public company, frequently cited above 50 percent.

Why so powerful? Two-sided network effects. Every merchant accepts them because every consumer carries them, and vice versa. A new network cannot easily break in. This is the classic moatmoatA lasting edge over competitors: a resource, capability or position they cannot easily replicate, letting a firm earn above-average returns over time.View full definition →.

The issuers: fat margins, real risk

Issuers capture the biggest single slice (interchange) and, on credit cards, also earn interest and fees. But they take the credit risk: if the cardholder does not pay, the issuer eats the loss. High reward, real exposure. Large issuers also have power because they choose which network to route on and can extract co-brand deals.

The acquirers and processors: the squeezed middle

This is where margin hides least. Acquiring and processing is increasingly commoditized. Big merchants (Amazon, Walmart, airlines) negotiate rates down toward cost. The function looks more like a utility: high volume, thin per-transaction margin, competing on price and reliability.

The exception is firms that escaped the commodity trap by bundling software. Which brings us to the disruptors.

How challengers changed the mapmapUsing software to automate repetitive marketing tasks and campaigns, enabling personalisation at scale across channels like email, web, and social.View full definition →

The old value chain assumed a bank on both ends. Fintech blew that open.

Stripe and Adyen collapsed the processor and acquirer roles into a single developer-friendly layer. They win by serving merchants that legacy acquirers found awkward: online platforms, marketplaces, subscription businesses. They still pay interchange to issuers and scheme fees to the networks. They did not overthrow the toll booth; they built a nicer on-ramp to it.

Square (Block) went after the smallest merchants, the coffee cart itself, with a flat simple rate and free hardware. It captured merchants that traditional acquirers ignored, then cross-sold lending and banking.

Buy Now Pay Later firms (Klarna, Affirm, Afterpay) inserted a new lender between shopper and merchant. Here the economics flip: the merchant often pays BNPL a higher fee than a card, sometimes 3 to 6 percent, because BNPL claims to lift conversion and basket size. BNPL captures margin by taking on short-term lending risk and by owning the checkout moment.

Regulation reshapes the split

Who captures the margin is not just market power. Regulators keep rewriting the rules.

• Europe: the EU Interchange Fee Regulation (IFR), in force since 2015, caps interchange at 0.2 percent for consumer debit and 0.3 percent for consumer credit. This is why European merchant fees are dramatically lower than US ones. The cap transferred margin away from issuers and toward merchants.
• US: the Durbin Amendment (part of the 2010 Dodd-Frank Act) caps debit interchange for large banks (assets over 10 billion dollars). Credit interchange remains uncapped, which is why US credit card fees stay high. The Fed proposed lowering the debit cap further; watch that space in 2026.
• PSD2 (the EU's revised Payment Services Directive) forced banks to open customer data via APIs, enabling account-to-account payments that bypass cards entirely. Its successor, PSD3, is progressing through the EU legislative process.

The direction of travel: regulators keep trying to shift margin from issuers and networks toward merchants and consumers. The networks keep finding new fee lines.

The next threat: skipping the rails entirely

The whole chain above assumes a card. Account-to-account (A2A) payments do not use one.

In A2A, money moves directly from the payer's bank account to the merchant's, over a real-time payment system. No interchange. No scheme fee. Examples: Pix in Brazil (run by the central bank, now dominant), UPI in India, and in the US the Federal Reserve's FedNow service, launched in 2023.

If A2A takes off in commerce, it threatens the two fattest slices: issuer interchange and network scheme fees. That is why Visa and Mastercard have been buying A2A and open-banking capabilities themselves. If you cannot beat the disruption, own it.

For merchants, the pitch is simple: pay far less than 2 percent. For issuers, it is an existential question: what replaces interchange revenue if shoppers stop swiping?

Reading any payments story through this lens

When you see a payments headline, ask three questions:

1. Which role is the company playing? Issuer, acquirer, network, processor, or a new lender like BNPL.
2. Do they carry risk or just take a toll? Toll takers (networks) have the best margins and the strongest moats. Risk takers (issuers, BNPL) earn more per transaction but can lose.
3. Who is trying to disintermediate them? A2A and regulation are both aimed at the same targets: interchange and scheme fees.

Key takeaways

• On a typical US card purchase, the issuer takes the largest slice via interchange (roughly two-thirds of the merchant fee), the network takes a small but extremely high-margin cut, and the acquirer/processor is the squeezed, near-utility middle.
• Visa and Mastercard are the toll booths: tiny per-transaction fees, enormous volume, no credit risk, defended by two-sided network effects. That is the best seat in the chain.
• Regulation directly moves the margin: the EU's IFR caps interchange far below US levels, and the Durbin Amendment caps only US debit, which is why credit card fees stay high in America.
• Fintechs mostly rebundled roles rather than destroying them: Stripe and Adyen fused acquiring and processing; BNPL inserted a new lender that charges merchants more.
• The real long-term threat is account-to-account payments (Pix, UPI, FedNow), which bypass interchange and scheme fees entirely, which is exactly why the networks are buying their way into that space.