Is Flat-Rate Processing Ever the Better Deal? When It Wins

Yes, sometimes. Flat-rate processing can be the better or the simpler deal for very small tickets, for brand-new businesses with very low volume, and for owners who will never read a statement. It stops being the better deal as tickets grow, and fastest for invoices and online sales. This guide shows where the line sits, with our arithmetic, a simple test you can run on your own last statements, and what to ask any provider.

The short answer

Flat rate can win on tiny in-person tickets. In the model behind NPS’s 2026 pricing study, an in-person seller with tickets around $15 and under saves little by moving to interchange pass-through.
It can also win on simplicity. A brand-new business with very low volume, or an owner with no time to manage statements, may be better served by one clear price.
It stops winning as tickets grow. The study’s model finds pass-through costs 19% to 31% less for online and invoice sales across average tickets from $15 to $2,500.
Our in-person arithmetic is labelled as ours. From the study’s listed inputs, the in-person gap against Square’s 2.6% plus 15 cents is about 6.5% at a $15 ticket and 19% to 25% from a $40 ticket upward.
The only number that settles it is your own statement. The test is below.

Which Model Wins

Flat rate vs. pass-through: where each wins

Small in-person tickets (~$15): Flat rateGap is only ~6.5%, hard to beat; Interchange pass-throughSaves little at this ticket size
Larger tickets ($40 and up): Flat rate19%, 25% more expensive in-person; Interchange pass-through19%, 25% less costly in-person
Online and invoice sales: Flat rateStarts higher: 3.3% + 30¢ (Square); Interchange pass-through19%, 31% less across $15 to $2,500 tickets
Statement simplicity: Flat rateOne headline price; Interchange pass-throughInterchange, network fees, markup on separate lines

Why a pass-through seller is telling you flat rate can win

Nationwide Payment Systems (NPS) sells interchange pass-through pricing, so we are not neutral. That is exactly why this page spells out the cases where flat rate is the sensible choice. If a page from a seller of pass-through only ever told you to switch, you would be right to doubt it. The study we cite, “The Flat-Rate Tax” (2026 Edition), was written by our CEO, Allen Kopelman. It is a model built from published rate schedules, not a survey. It lists every input so anyone can rerun it, and it says plainly that flat rate can still be the better deal in some cases.

First, what flat rate and pass-through mean

A flat-rate processor charges one headline price on every card, whatever the card is. As read on Stripe’s pricing page on November 13, 2026, Stripe’s price is 2.9% plus 30 cents per successful domestic card transaction. As read on Square’s fees page on November 13, 2026, Square lists 2.6% plus 15 cents for tap, dip or swipe, and 3.3% plus 30 cents for online sales and invoices. Prices change, so open each page for today’s price.

Flat-Rate Prices

What flat-rate processors charge per sale

Square in-person2.6% + 15¢Tap, dip or swipeAs read on Square’s fees page on November 13, 2026
Square online / invoices3.3% + 30¢Online sales and invoicesAs read on Square’s fees page on November 13, 2026
Stripe2.9% + 30¢Per successful domestic card transactionInvoicing adds 0.4% per paid invoice; manually entered cards add 0.5%. As read on Stripe’s pricing page on November 13, 2026

Prices change, open each provider’s page for today’s price.

Interchange pass-through, also called interchange-plus, passes along what the card networks and issuing banks charge on each card and adds one disclosed markup. A debit card costs less than a rewards credit card, and you can see both on your statement. We explain the models in where Stripe fees actually go.

When flat rate is the better or simpler deal

1. Very small in-person tickets, around $15 and under

Every card payment carries a fixed per-item piece. On Square’s in-person price it is 15 cents, and on Stripe’s price it is 30 cents. On a small sale, that fixed piece is a large share of the fee, and the same fixed pieces exist on the pass-through side too. That squeezes the gap between the two models. In our arithmetic from the study’s listed inputs, the in-person gap against Square’s 2.6% plus 15 cents is only about 6.5% at a $15 ticket, against 19% to 25% from a $40 ticket upward.

Here is made-up math to show the method, not a promise. A coffee cart that runs 200 card sales a month at $15 pays Square’s in-person price of 54 cents per sale, which is about $108 a month. A 6.5% gap on that is about $7 a month in the model. If a pass-through quote adds a monthly fee or a statement fee, a gap that small can disappear. Ask about those lines before you decide.

2. Brand-new businesses with very low volume

The study itself says flat rate is simple for brand-new businesses with very low volume. When you are processing a few hundred dollars a month, the difference in dollars is small, and your time is better spent finding customers. A flat price you can read in one line is a fair place to start. Revisit it once volume and ticket size grow.

3. Owners with no time to manage statements

Pass-through is more transparent, but transparency only helps if somebody reads the statement. If you know you will not read it, the one-line price of flat rate has real value. The cost of that convenience is what the rest of this page is about, so make the choice on purpose and put a date on the calendar to check it again.

When flat rate stops being the better deal

Higher in-person tickets

Once the ticket moves up, the fixed pieces matter less and the percentage matters more. Our arithmetic from the study’s inputs puts the in-person gap against Square’s 2.6% plus 15 cents at 19% to 25% from a $40 ticket upward. Made-up math to show the method: a shop that runs 250 sales a month at $40 pays about $1.19 per sale at Square’s in-person price, which is about $297.50 a month. A 19% to 25% gap on that is roughly $57 to $74 a month, or about $680 to $890 a year. That is a model result, not a promise, and your own card mix will move it.

Invoices and online sales

For online and invoice sales it finds pass-through costs 19% to 31% less across average tickets from $15 to $2,500. Its example is $50,000 a month in invoices at a $150 average ticket, which keeps about $6,100 a year in the model. Flat-rate prices for remote sales also start higher. As read on Square’s fees page on November 13, 2026, online sales and invoices are 3.3% plus 30 cents, against 2.6% plus 15 cents in person.

Stripe’s page adds more. As read on Stripe’s pricing page on November 13, 2026, Invoicing adds 0.4% per paid invoice, and manually entered cards add 0.5%. Our arithmetic on one $150 invoice: 2.9% plus 30 cents is $4.65, and the 0.4% adds 60 cents, for $5.25. We go through it line by line in cheapest card processing for invoices and payment links.

Larger sales of any kind

At a $500 sale, 2.9% plus 30 cents is $14.80, and at $2,500 it is $72.80 (our arithmetic from Stripe’s listed price). The percentage does most of the work at those sizes, which is why a flat rate has the least room to compete there.

Why the gap appears

A flat rate charges the same percentage on a low-cost debit card as on a rewards credit card. Under federal rules, interchange on debit cards from large banks is capped at 0.05% of the sale plus 21 cents, with a 1 cent fraud adjustment. The cap applies to large-bank debit only. It does not apply to small-bank debit cards, and we never assume a card is covered just because it is debit. Interchange also varies by card type. Business and commercial cards can cost more, and Level 2 and Level 3 data can lower them. Our post on whether the debit cap applies to small-bank cards covers the detail.

A simple test you can run on your own last statements

You need two or three recent processor statements and an hour at most. This works whether you are on a flat-rate processor today or already on pass-through.

Find your total card volume for the month. That is the dollars you ran through cards, before fees.
Find your total fees for the same month. Include monthly, statement, gateway, invoice, dispute and any other charge, not only the percentage line.
Divide fees by volume. That is your effective rate. Our guide to reading your merchant statement shows where each number sits.
Work out your average ticket. Divide volume by the number of sales. If it is around $15 or under, flat rate may be hard to beat. If it is $40 or more, there is probably something to compare.
Split your volume by how it was taken. In person, online and invoices are priced differently on some flat-rate plans, so average them separately.
Price the same month on a written quote. Ask a provider to price your actual statement, line by line, and put both totals side by side.
Multiply the difference by twelve. A few dollars a month may not be worth a change. A few hundred probably is.

Your Statement Test

Run this test on your last statements

Find your total card volumeThe dollars you ran through cards, before fees.
Find your total feesInclude monthly, statement, gateway, invoice, dispute and any other charge, not only the percentage line.
Divide fees by volumeThat is your effective rate.
Work out your average ticketDivide volume by the number of sales.
Split your volume by how it was takenIn person, online and invoices are priced differently on some flat-rate plans, so average them separately.
Price the same month on a written quoteAsk a provider to price your actual statement, line by line, and put both totals side by side.
Multiply the difference by twelveA few dollars a month may not be worth a change.

Use two or three statements if you can, a holiday month and a slow month can look very different.

If the flat-rate side comes out close, keep it. That is a good answer and costs you nothing. For a wider view of the cost question, see cheapest payment processing in 2026, and for a provider-by-provider comparison, how much you are really paying on Stripe, Square, PayPal or QuickBooks.

A made-up shop with two kinds of tickets (our arithmetic)

Most real businesses do not have one ticket size. Here is made-up math to show the method, not a promise and not a typical shop. Say a counter-service shop runs 300 in-person card sales a month at $15 and 100 in-person card sales a month at $60. At Square’s in-person price of 2.6% plus 15 cents, a $15 sale costs 54 cents, so the 300 small sales cost $162. A $60 sale costs $1.71, so the 100 larger sales cost $171. The month comes to $333 in fees.

Now apply the study’s in-person gaps to each half, as our arithmetic and not as a quote. About 6.5% on the $162 is about $10.53. A range of 19% to 25% on the $171 is about $32.49 to $42.75. Together that is about $43 to $53 a month, or about $516 to $639 a year. Almost all of the gap comes from the $60 sales, even though they are only a quarter of the payments. That is the useful lesson. Split your payments by ticket size before you decide, because a flat rate can be fine for the small ones and costly for the large ones.

It also shows why a monthly fee in a pass-through quote matters. A statement or gateway fee of even $15 a month would eat into a gap of that size, so read every line of a written quote before you compare totals.

Mistakes to avoid when you compare

Comparing one headline number with another. A flat rate is one line. A pass-through quote has several. Put both on the same month of your own volume and compare dollars.
Using one month only. A holiday month and a slow month can look very different. Use two or three statements if you can.
Ignoring the cost of leaving. Ask whether your current agreement has an early termination fee, and whether any equipment is leased or owned.
Ignoring the cost of staying. Doing nothing is a choice with a price. Write down what you pay in a year so the comparison is fair.
Forgetting to check again. Ticket size and volume change as a business grows. A flat rate that fit last year may not fit next year, so put a date on the calendar.

If you do decide to move, ask the new provider to put the markup, the monthly fees and the contract terms in writing before you sign. Keep your old setup running until the new one has handled a few real payments, so you never go a day without a way to take a card.

What to ask any provider, flat rate or not

What is the full price for in-person, online and invoice payments, each on its own line?
Is there a fee just for sending an invoice or a payment link?
What do keyed and card-on-file payments cost?
What are the dispute fees, and are they refunded if I win?
Are there monthly, statement, gateway or PCI fees?
If the pricing is interchange plus, what is the markup, in writing, and is it fixed?
Can I leave, and what does leaving cost?
Can I see a sample statement with every fee on its own line?

If any answer is “it depends,” ask on what. A clear answer lets you do the arithmetic yourself. We cover specific business types in restaurants, retail stores and growing online stores.

Before You Sign

Ask every provider these questions

Ask for the full price for in-person, online and invoice payments, each on its own line
Ask whether there is a fee just for sending an invoice or a payment link
Ask what keyed and card-on-file payments cost
Ask what the dispute fees are, and whether they are refunded if you win
Ask about monthly, statement, gateway or PCI fees
Ask for the markup in writing and confirm it is fixed (interchange-plus accounts)
Ask whether you can leave, and what leaving costs
Ask to see a sample statement with every fee on its own line

You can also run your own numbers through our savings calculator.

To see how other providers price, read our guide to the best payment processors compared by business type.

Who wrote this, and where NPS fits

Nationwide Payment Systems (NPS) publishes this guide. We are a payments company based in Fort Lauderdale, Florida, in business since 2001, and we sell merchant accounts and invoicing software, so we are not neutral. We offer interchange pass-through pricing, ACH, a payment gateway and Smart Invoicing, and we also offer flat-rate options. We do not publish a price list. The study we cite was written by our CEO. NPS offers a free statement review. Browse more in our payments guides.

We are not the right fit for every business. If your tickets are very small, your volume is very low or you want one simple price and nothing else to manage, a flat-rate setup may cost you less in money or in time.

Bottom line

Flat rate is a fair deal for very small in-person tickets, for brand-new sellers with very low volume, and for owners who will not read statements. It is a worse deal as tickets grow, and most of all for invoices and online sales, where the study’s model finds 19% to 31% lower costs on pass-through. Divide your fees by your volume, price the same month on a written quote, and decide from the difference. If you want a second opinion, you can contact our team.

Frequently asked questions

Is flat-rate processing ever the better deal?

Yes, in some cases. In our study’s model, in-person sellers with very small tickets, around $15 and under, save little by moving to interchange pass-through, and flat rate is simple for brand-new businesses with very low volume. Run your own numbers.

What does Stripe’s 2.9% + 30 cents cost on a small sale?

As read on Stripe’s pricing page on November 13, 2026, the price is 2.9% plus 30 cents per successful domestic card transaction. Our arithmetic: on a $15 sale that is about 73.5 cents, or 4.9%, and on a $40 sale it is $1.46, or 3.65%. That is made-up math to show the method, not a promise about your account. Check Stripe’s own page for today’s price.

Is flat rate easier than interchange pass-through?

Often, yes. With flat rate you see one headline price. With pass-through you see interchange, network fees and a markup on separate lines, which takes a little time to read. If you will not look at statements at all, that simplicity has real value, but you still pay for it on larger sales.

At what ticket size does flat rate stop being competitive?

There is no single line, because it depends on card mix and channel. In our arithmetic from the study’s inputs, the in-person gap against Square’s 2.6% plus 15 cents is about 6.5% at a $15 ticket and 19% to 25% from a $40 ticket upward. For online and invoice sales the study’s model shows 19% to 31% across $15 to $2,500 tickets.

How do I test my own statements?

Add up the total fees and the total card volume for a month, divide fees by volume to get your effective rate, and note your average ticket. Then compare that rate with what a written quote from another provider would have cost on the same month. Our steps are below.

Does the debit cap make pass-through cheaper on every debit card?

No. As the study explains, the cap of 0.05% plus 21 cents, with a 1 cent fraud adjustment, applies to large-bank debit cards, not small-bank debit cards. Interchange also varies by card type, and business and commercial cards can cost more.

Does NPS review my current statement for free?

Yes. NPS offers a free statement review.

Is Flat-Rate Processing Ever the Better Deal? When 2.9% + 30 Cents Wins