For most established businesses, interchange-plus pricing costs less than flat-rate pricing, because you pay the card networks' actual cost plus a fixed, visible markup instead of one blended rate set high enough to cover the most expensive cards. Flat-rate pricing still wins in a few situations, mainly very low volume, a brand-new business or a markup quote with a high per-transaction fee. This interchange plus vs flat rate comparison walks through how each model works, runs the math on two realistic examples and shows how to tell which one fits your shop.
Key takeaways
- Flat-rate pricing charges one rate for every card (for example, Square's standard in-person rate of 2.6% + 15¢). It is simple, but you pay the same on a cheap debit card as on a premium rewards card.
- Interchange-plus pricing passes through the real interchange and network fees and adds a disclosed markup, such as 0.25% + 10¢. Every layer is visible on your statement.
- In our illustrative example, a shop running $40,000 a month in person paid about $366 less per month on interchange-plus than on a 2.6% + 15¢ flat rate.
- For very small tickets, the per-transaction fee matters more than the percentage, and a poorly negotiated interchange-plus quote can cost more than flat rate.
- Tiered pricing is the third model, and it is usually the hardest to audit.
How each pricing model works
Every card payment carries the same underlying costs no matter who processes it: interchange paid to the bank that issued the card, assessments paid to the card network, and the processor's markup. Our guide to credit card processing fees breaks those layers down in detail. Pricing models differ only in how those three layers are packaged and shown to you.
Flat-rate pricing
With flat-rate credit card processing, the processor quotes one price per payment method and absorbs the difference between that price and the real cost. Published examples as of this writing:
- Square (standard Free plan): 2.6% + 15¢ in person, 3.3% + 30¢ online or by invoice, 3.5% + 15¢ for keyed or card-on-file payments. Paid plans lower the in-person rate slightly.
- Stripe (standard pricing): 2.9% + 30¢ for domestic online cards, 2.7% + 5¢ in person on Stripe Terminal, with surcharges for manually entered and international cards.
The appeal is obvious: you can predict the cost of any sale in your head, there is usually no monthly fee, and sign-up is fast. The catch is that the rate has to be high enough to stay profitable on the most expensive cards the processor sees, so on cheaper transactions the processor keeps a much larger margin.
Interchange-plus pricing
Interchange plus pricing (also called "cost-plus" or "pass-through") bills you the actual interchange and network fees for each transaction, then adds a fixed markup written into your agreement, for example interchange + 0.25% + 10¢. The markup stays the same whatever card the customer uses; only the pass-through cost moves.
That pass-through cost varies a lot. Visa's published U.S. rates effective April 18, 2026 put card-present consumer credit between about 1.43% + 10¢ for basic cards and 2.30% + 10¢ for top-tier Infinite cards. Debit from large banks is capped by the Federal Reserve's Regulation II at 0.05% + 21¢, plus a one-cent fraud-prevention adjustment for eligible issuers. On flat rate, all of those cards cost you the same. On interchange-plus, the cheap ones are actually cheap.
Tiered pricing, briefly
Tiered pricing sorts transactions into "qualified," "mid-qualified" and "non-qualified" buckets, each with its own rate. The processor decides which cards land in which bucket, and rewards cards and keyed sales tend to fall into the expensive tiers. It looks simple on a rate sheet but is the hardest of the three to verify on a statement. If you are on tiered pricing today, comparing it against an interchange-plus quote is usually the quickest win.
Interchange-plus vs. flat-rate: side by side
| Flat-rate | Interchange-plus | |
|---|---|---|
| What you pay | One blended rate per payment method | Actual interchange + network fees + fixed markup |
| Cost on a regulated debit card | Same as a premium rewards card | Much lower: debit interchange is capped |
| Statement transparency | Simple, but you cannot see the processor's margin | Longer, but every layer is itemized and auditable |
| Monthly fees | Often none | Sometimes a small monthly or PCI fee; ask for all fees in writing |
| Network rate changes | Processor keeps any decrease unless it lowers your rate | Passed through to you automatically, up or down |
| Best fit | New, seasonal or very low-volume businesses | Established businesses, larger tickets, higher debit share |
Worked example: which saves you more?
The only honest way to compare is to price the same month of sales both ways. The figures below are illustrative: we assumed a blended credit interchange of 1.80% + 10¢ (inside Visa's published card-present range), large-bank regulated debit at 0.05% + 22¢, and network assessments of roughly 0.14% of volume. Your real numbers depend on your card mix, so treat this as a method, not a quote.
Example 1: a shop doing $40,000 a month in person
800 transactions with a $50 average ticket, 40% on debit and 60% on credit, compared at 2.6% + 15¢ flat versus interchange + 0.25% + 10¢.
| Line item | Flat rate (2.6% + 15¢) | Interchange-plus (+0.25% + 10¢) |
|---|---|---|
| Debit interchange (320 sales, $16,000) | Included in flat rate | $78.40 |
| Credit interchange (480 sales, $24,000) | $480.00 | |
| Network assessments (~0.14%) | $56.00 | |
| Processor markup | Included in flat rate | $180.00 |
| Total monthly fees | $1,160.00 | $794.40 |
| Effective rate | 2.90% | 1.99% |
The difference is about $366 a month, or roughly $4,400 a year, before any monthly fees on the interchange-plus account. Even if you add a modest monthly fee, interchange-plus comes out well ahead at this volume. The gap widens as your debit share grows, because flat rate charges a debit card the same 2.6% + 15¢ that interchange-plus charges at well under 1%.
Example 2: a coffee shop doing $12,000 a month on $6 tickets
2,000 transactions, half debit and half credit, with the same interchange assumptions. Here the fixed per-transaction pieces dominate: a regulated debit card costs about 22¢ in interchange alone, which is 3.7% of a $6 sale.
| Pricing | Monthly fees | Effective rate |
|---|---|---|
| Flat rate, 2.6% + 15¢ | $612.00 | 5.10% |
| Interchange + 0.25% + 10¢ | $677.80 | 5.65% |
| Interchange + 0.25% + 5¢ | $577.80 | 4.82% |
This is the case where flat rate can win. At very small tickets, a 10-cent markup on top of real interchange costs more than a 15-cent all-in flat fee. Cut the per-item markup to 5 cents and interchange-plus pulls ahead again. The lesson for coffee shops and other small-ticket businesses: negotiate the cents, not just the percentage, and ask whether your processor offers small-ticket interchange programs where they apply.
Quick test: divide last month's total processing fees (every line, including monthly and PCI fees) by your total card sales. If that effective rate sits near your flat rate on in-person sales with a meaningful share of debit, it is worth getting an interchange-plus quote for the same month.
When flat-rate pricing makes sense
Flat rate is not a bad product; it is a simple one. It is often the right choice when:
- You are just starting out. Fast approval, no long contract and an all-in-one point of sale can be worth a few extra basis points while you find your footing.
- Your volume is low or seasonal. A pop-up, farmers market stand or side business may run a few thousand dollars a month, where any monthly fee on interchange-plus can erase the savings.
- Your tickets are tiny and the interchange-plus quote has a high per-item fee, as Example 2 shows.
- Predictability matters more than the last dollar. Some owners value knowing exactly what each sale costs.
Some flat-rate providers also offer custom pricing to larger accounts; Stripe, for example, lists interchange-plus as part of its custom pricing for businesses with large volumes. If you have outgrown flat rate, ask.
When interchange-plus saves you more
- You process more than a few thousand dollars a month and expect to grow.
- Your average ticket is mid-sized or large, as in most auto repair, retail and restaurant businesses, so the percentage markup matters more than the cents.
- A good share of customers pay with debit. Flat rate charges debit the same as credit; interchange-plus does not.
- You want to audit your bill. With each layer itemized, you can confirm the markup you were promised is the markup you were charged, and spot rate creep.
- You want industry changes passed through. A proposed Visa and Mastercard settlement that received preliminary court approval in June 2026 would trim average credit interchange by about 10 basis points for five years, though final approval was still pending and objections had been filed as of September. If those reductions take effect, an interchange-plus account sees them automatically. A flat-rate account sees them only if the provider chooses to lower its rate.
What to ask before you sign either one
Whichever model you choose, get these answers in writing. Our guide to choosing a merchant services provider covers contract terms in more depth.
- What is the exact markup (percentage and per-transaction fee), and is it fixed for the life of the agreement?
- What monthly, annual, PCI, statement, batch or gateway fees apply?
- Is there a contract term, early termination fee or equipment lease?
- For flat rate: what are the separate rates for keyed, online, card-on-file and international cards?
- For interchange-plus: will my statement show interchange by card category so I can verify it?
- How fast are deposits funded, and are there holds or reserves?
If you are also weighing a surcharge or cash discount program to offset costs, read our guide to credit card surcharge rules in 2026 first. Colorado, for example, caps credit card surcharges at 2% under C.R.S. § 5-2-212, which is lower than the network maximum.
The bottom line
Flat-rate pricing buys simplicity. Interchange-plus buys transparency, and for most businesses past the startup stage, lower total cost. The right answer for your shop comes from your own numbers: your volume, average ticket and debit-to-credit mix. Run last month's sales through both models, or see what you could save with a side-by-side estimate. If you would rather not do the math, send us a recent statement for a free statement review and we will show you, line by line, what you are paying today and what the same month would cost on interchange-plus.
Frequently asked questions
Is interchange-plus pricing cheaper than flat rate?
Usually, for established businesses. Interchange-plus passes through the real cost of each card plus a fixed markup, so cheaper cards such as regulated debit cost much less. Flat rate can be cheaper for very low-volume businesses or very small tickets if the interchange-plus quote carries a high per-transaction fee.
What is a good interchange-plus markup?
There is no single standard. Markups depend on volume, ticket size and risk. What matters is that the percentage and per-transaction fee are fixed in writing, and that the total effective rate, including all monthly fees, beats your current cost on the same month of sales.
What is the difference between flat rate and tiered pricing?
Flat rate charges one rate for every card of a given payment method. Tiered pricing sorts cards into qualified, mid-qualified and non-qualified buckets at different rates, and the processor decides which bucket each card falls into. That makes tiered pricing harder to audit than either flat rate or interchange-plus.
When should a business switch from flat rate to interchange-plus?
A good time to compare is when monthly card volume reaches the low five figures, when your average ticket is $25 or more, or when a meaningful share of customers pay with debit. Price one real month of sales both ways, including every monthly fee, before you decide.
Why does my flat rate stay the same when card fees go down?
A flat rate is set by the processor, not the card networks. When interchange or network fees change, the processor decides whether to adjust your rate. On interchange-plus, network changes pass through to you automatically because you pay the actual interchange.
Sources and further reading
- Visa USA interchange reimbursement fees (effective April 18, 2026)
- Federal Reserve: Regulation II (debit card interchange)
- Square: What are Square's fees?
- Stripe pricing
- Payments Dive: Court approves Visa-Mastercard settlement (June 2026)
Published rates change; check each provider's current pricing. General information, not legal or financial advice.