A seasonal business should compare flat rate and interchange plus on 12 months of statements, not 3. In the made-up year in this guide, a flat rate of 2.9% plus 30 cents cost $9,052 on $292,000 of sales, a 3.1% effective rate, and the four slowest months cost only $930 of it, so a look at the wrong three months can mislead you badly. This guide explains flat rate and interchange plus in plain words, lists the questions to ask about monthly fees and minimums, and says when a flat rate is perfectly fine.
Made-up year cost
What flat rate cost on $292,000 of sales
- Full year$9,052Flat-rate fees at 2.9% + 30 centsEffective rate of 3.1%; four slowest months cost only $930 combined
- Model savings$1,720 to $2,806Less with pass-through, per study model19% to 31% less; depends on card mix, ticket size, written markup and every fixed fee
The short answer
- A percentage-only price moves with your sales. As read on Stripe’s pricing page on November 13, 2026, Stripe lists 2.9% plus 30 cents per successful domestic card transaction. Check that page for today’s price.
- Fixed charges do not move. Any monthly fee, monthly minimum or statement fee is paid in slow months too. Ask every provider about each one, in writing.
- Compare with 12 months of statements, not 3. Three months can fall entirely inside your peak or your slow season.
- In our study’s model, pass-through costs 19% to 31% less than flat rate for online and invoice sales. It is a model, and NPS sells pass-through, so we are not neutral.
- Flat rate is sometimes the right answer. We say when, below.
What pass-through means, in plain words
Every card payment has a few layers of cost. The largest layer is interchange, a fee set by the card networks that goes to the bank that issued the customer’s card. A smaller layer is the card network’s own fees. The last layer is what your processor keeps for itself, its markup.
A flat-rate processor combines all three layers into one headline price, for example 2.9% plus 30 cents. You pay the same price whether the customer used a plain debit card or a premium rewards card. Allen Kopelman, the CEO of NPS, calls the other approach pass-through. Under pass-through, which you may also see called interchange plus, the real interchange and network fees for each payment are passed on to you at cost, and the processor adds one markup written in your agreement. In other words, you see the cost of each card and the processor’s cut as separate things, instead of one blended number.
Pricing models
Flat rate vs. pass-through for a seasonal business
- What you pay per transaction
- Flat rateOne headline price, e.g. 2.9% + 30 cents
- Pass-through (interchange plus)Real interchange + network fees + one written markup
- Slow-month behavior
- Flat ratePercentage shrinks; fixed charges do not
- Pass-through (interchange plus)Percentage shrinks; ask about any fixed charges
- Cost vs. the other model
- Flat rate$9,052 on $292,000 in the made-up year
- Pass-through (interchange plus)Model suggests $6,246 to $7,332 on same sales
In our study’s model, pass-through costs 19% to 31% less than flat rate for online and invoice sales, and flat rate can still be the better choice for small or new businesses.
Neither model is magic. Interchange varies by card type, and business and commercial cards can cost more. Level 2 and Level 3 data can lower some of them. NPS explains how the models compare in where Stripe fees actually go.
Why seasonal sales change the question
A business with steady monthly sales can look at one month and know the year. A seasonal business cannot. The same price list produces very different bills across the calendar, and the fixed parts of a bill, if there are any, weigh far more in the months when you sell little.
Think of two kinds of charges. A percentage charge is like a commission: it shrinks to almost nothing in a month with almost no sales. A fixed charge is like rent: it arrives on the first of the month whether the shop was busy or empty. A pricing model that looks cheap in July can look different in January if rent-like charges are attached to it. That is the reason for the questions in the next section.
Questions to ask any provider about slow months
We are not saying any particular provider charges these. We are saying a seasonal business should ask, because the answer changes the yearly total. Get each answer in writing, and ask for a sample statement where every fee has its own line.
- Is there any monthly fee? If so, how much, and is it charged in a month with no sales?
- Is there a monthly minimum? What happens in a month when your fees fall below it? Is the difference billed to you?
- Is there a statement fee? Is it charged every month?
- What are the gateway, PCI and other recurring fees, and do they continue in slow months?
- What happens if I pause or close for part of the year? Can the account stay open at no cost, and what does reopening involve?
- What is the markup? Is it fixed in the agreement for the full term?
- What does the contract say about ending it? Is there an early termination fee?
- What do disputes cost? As read on Stripe’s pricing page on November 13, 2026, Stripe lists $15.00 for each dispute received and $15.00 for each dispute you respond to manually, refunded for won disputes.
If an answer is “it depends,” ask on what. A provider that answers clearly makes your arithmetic easy. NPS publishes no price list, so you will need to ask us the same questions.
Before you sign
Questions to ask any provider about slow months
- Ask whether there is any monthly fee, and if it is charged in a month with no sales
- Ask about any monthly minimum and what happens when your fees fall below it
- Ask whether there is a statement fee charged every month
- Ask what gateway, PCI and other recurring fees continue in slow months
- Ask what happens if you pause or close for part of the year, and what reopening involves
- Ask for every answer in writing and for a sample statement where every fee has its own line
How to compare using 12 months of statements
You need your last 12 monthly statements, one for each month, and a simple table. Here is the method.
- Collect 12 statements. If you have been in business less than a year, use every month you have and say so when you ask for a quote.
- For each month, write down three numbers: total card sales, number of transactions, and total fees paid. Count every line, including monthly, statement, gateway and dispute lines.
- Divide fees by sales for each month. That is your effective rate for the month. In a month with a fixed charge and low sales it will look higher. That is the point of doing it by month.
- Add the 12 months. The yearly total is the number that changes decisions.
- Ask for a quote based on the same 12 months, not on your best month or your average month. Ask the provider to show the monthly and yearly result, not only a rate.
- Compare totals, not headlines. A lower rate with a monthly minimum can cost more over a year than a slightly higher rate with nothing fixed.
12-month comparison
How to compare using 12 months of statements
-
Collect 12 statementsIf you have been in business less than a year, use every month you have and say so when you ask for a quote.
-
Write down three numbersFor each month: total card sales, number of transactions, and total fees paid.
-
Divide fees by salesThat is your effective rate for the month.
-
Add the 12 monthsThe yearly total is the number that changes decisions.
-
Ask for a quote on the same 12 monthsAsk the provider to show the monthly and yearly result, not only a rate.
Why 12 and not 3? Suppose you take the last three months and multiply by four. If those three months were your busiest, you will overstate your yearly cost and may chase savings that are too large. If they were your slowest, you will understate your cost and may miss a real difference. The worked year below shows both mistakes with numbers. Our guide on how to read your merchant statement walks through each line.
A made-up year with a peak and slow months (our arithmetic)
This is made-up math to show the method, not a promise and not a real business. We invented a business that sells online and by invoice with an average ticket of $150. Its sales swing from $6,000 in its slowest month to $60,000 in its busiest. We priced every month at Stripe’s listed 2.9% plus 30 cents, as read on Stripe’s pricing page on November 13, 2026, and checked the arithmetic with a script.
- January: $8,000 in sales, about 53 payments, $248 in fees.
- February: $8,000, about 53 payments, $248.
- March: $12,000, 80 payments, $372.
- April: $20,000, about 133 payments, $620.
- May: $35,000, about 233 payments, $1,085.
- June: $60,000, 400 payments, $1,860.
- July: $60,000, 400 payments, $1,860.
- August: $45,000, 300 payments, $1,395.
- September: $20,000, about 133 payments, $620.
- October: $10,000, about 67 payments, $310.
- November: $8,000, about 53 payments, $248.
- December: $6,000, 40 payments, $186.
For the year, that is $292,000 in sales and $9,052 in flat-rate fees, an effective rate of 3.1%. Two things stand out. First, a pure percentage price behaves well in slow months: the four slowest months (January, February, November and December) cost $930 combined, while June and July cost $3,720. Second, the year is lopsided. Two months produce about 41% of the fees.
The three-month trap
Now see what happens if this business compares on only three months. The busiest three months (June, July and August) cost $5,115 in flat-rate fees. Multiply by four and you get $20,460 a year, more than twice the real $9,052. The slowest three months (October, November and December) cost $744. Multiply by four and you get $2,976, less than a third of the real number. The same business, the same statements, and two very different answers. That is why we ask for 12 months.
Adding the study’s pass-through finding (a model)
Our study, NPS’s 2026 pricing study, is called “The Flat-Rate Tax” and was written by Allen Kopelman, CEO of NPS. It is a model built from published rate schedules, not a survey. It finds that interchange pass-through costs 19% to 31% less than flat rate for online and invoice sales across average tickets from $15 to $2,500.
Apply that range to our made-up year, and the model suggests pass-through fees of about $6,246 to $7,332, which is about $1,720 to $2,806 less than the $9,052 flat-rate total. That is a model applied to invented sales, not a quote and not a promise. The real number depends on your card mix, your ticket size, the written markup and every fixed fee. If a provider adds a monthly fee, a monthly minimum or a statement fee, subtract it from the savings before you decide. A fixed fee multiplied by 12 can erase a percentage saving, especially for a business with a small year.
The study gives one more example for scale: $50,000 a month in invoices at a $150 average ticket keeps about $6,100 a year. That is a steady business. A seasonal business with the same yearly total can compare very differently, which is why the 12-month table matters more than any example.
When flat rate is fine for a seasonal business
We sell pass-through, so you should hear the other side from us too. A flat rate can be the better choice when:
- Your yearly card volume is small. A percentage saving on a small total is a small number, and your time has value.
- You are brand new. The study says flat rate can win for new, very low-volume businesses. Start simple, then compare when you have 12 months of statements.
- Your in-person tickets are tiny. The study says flat rate can still win at around $15 and under in person. Our arithmetic from the study’s listed inputs puts in-person pass-through at about 6.5% less than Square’s listed 2.6% plus 15 cents at a $15 ticket, and about 19% to 25% less from a $40 ticket upward. Those are our figures, built from the study’s inputs.
- You value a simple start. If you want to begin quickly, ask each provider how long setup takes and compare that with what you would save.
- The provider you are comparing has fixed charges that outweigh the percentage savings. Run the 12 months. If the yearly total is higher, stay.
For some businesses the right answer is to stay on flat rate now and revisit after one full season. For others, especially those with larger tickets or mostly online and invoice sales, a 12-month comparison is worth doing. Related reading: cheapest payment processing in 2026, how much you are really paying on Stripe, Square, PayPal or QuickBooks, the restaurant version, what a retail store saves leaving Square, and invoices and payment links for a service business.
One more factor for debit-heavy sales: the federal cap on debit interchange (0.05% plus 21 cents, with a 1 cent fraud adjustment) applies to large-bank debit cards only, not to small-bank debit. Read whether the debit cap applies to small-bank cards before assuming it helps you.
You can also run your own numbers through our savings calculator.
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 volume is small, or a flat rate already fits your year, a simpler setup may cost you less.
Bottom line
For a seasonal business, the winning move is to compare whole years, not good months. Pull 12 months of statements, add every fee, and ask each provider about monthly fees, minimums and statement fees in writing. In our study’s model, pass-through costs 19% to 31% less than flat rate for online and invoice sales, and flat rate can still be the better choice for small or new businesses. If you would like a second opinion on your own 12 months, you can contact our team.
Frequently asked questions
What is the difference between flat rate and interchange plus for a seasonal business?
A flat rate charges one headline price on every card payment, so your fees rise and fall with your sales. Interchange plus, which NPS also calls pass-through, charges the real card-network cost of each payment plus one written markup. For a seasonal business the bigger question is often what else is on the bill in slow months, so ask each provider about monthly fees, minimums and statement fees.
Does flat-rate pricing cost less in slow months?
A percentage-only price does shrink when sales shrink. In our made-up year above, a $6,000 December costs $186 in Stripe’s listed 2.9% plus 30 cents. That is our arithmetic to show the method, not a promise. Any monthly fee or minimum on top would not shrink, so ask about those before you sign.
What should I ask a provider about monthly fees and minimums?
Ask whether there is any monthly fee, any monthly minimum, any statement fee, and what happens in a month when your sales are very low or zero. Ask for the answers in writing and for a sample statement. Do not assume any provider has or lacks these charges until you see the agreement.
How many months of statements should I use to compare?
Use 12 months. Three months can land entirely in your peak or entirely in your slow season, and multiplying either by four gives a wrong yearly number. In our made-up year, scaling the busiest three months by four overstates the year by more than two times.
Can a seasonal business save with interchange plus?
In our study’s model, interchange pass-through costs 19% to 31% less than flat rate for online and invoice sales across average tickets from $15 to $2,500. The study is a model from a company that sells pass-through, not a survey, so test it on your own 12 months of statements.
When is flat rate the better choice for a seasonal business?
Flat rate can win when your volume is very small, when you are brand new, when your average in-person ticket is around $15 and under. Compare your own 12 months before deciding.
Does NPS offer a statement review?
Yes. NPS offers a free statement review.
