Almost every online payment processor charges some version of 2.9% + 30¢, and almost none of them arrived at it by calculation. It is a convention — a reference price that became the thing every other price is compared against.
What the number has to cover
A flat rate is a bundle. Out of that 2.9% the processor pays interchange to the customer's bank, an assessment to the card network, and its own costs — fraud, chargebacks, infrastructure, support — before anything is margin.
| Component | Paid to | Roughly |
|---|---|---|
| Interchange | The issuing bank | $1.50 – $2.10 |
| Network assessment | Visa / Mastercard | $0.13 – $0.15 |
| Everything else | The processor | The remainder |
On a cheap debit transaction the processor keeps most of the fee. On an expensive corporate card it keeps very little, and can lose money outright. Flat-rate pricing is partly an insurance product, and the premium is the averaging.
Why it stuck
Reference prices are self-reinforcing. Once a buyer has a number in their head, a seller has two options: match it, or spend the sales conversation explaining the difference. Matching is cheaper.
It also makes comparison shopping feel unnecessary. If four providers all quote 2.9% + 30¢, the rate stops being a decision and the choice moves to product, documentation and brand — which suits the incumbents.
The half nobody negotiates
Attention goes to the percentage. The fixed 30¢ is treated as a rounding error, and for a $200 transaction it nearly is — 0.15%.
At $10 it is 3% on its own, more than the headline rate. For any business selling low-ticket items, the fixed fee is the larger number and the one worth arguing about. We wrote that up separately in when 30¢ costs more than the percentage.
What to do with this
- Stop treating it as a floor. It is a convention, not a cost. Providers below it exist and are not doing anything exotic.
- Compare on effective rate, using your real average transaction — the fee impact calculator shows the curve.
- Weight the fixed fee by your ticket size. Below $10.34 it is literally the larger of the two components, and below roughly $75 it is what decides between two providers.
- Check what else is bundled. Some providers price subscriptions, invoicing or fraud tooling separately on top.
Sources
- Published pricing pages for Stripe, PayPal, Square and others, September 2026.
- Visa and Mastercard published US interchange rate schedules.
- Durbin Amendment to the Dodd-Frank Act, 2010, effective 2011 — the regulated debit interchange cap.
GOOD QUESTIONS
Frequently asked
Why do so many processors charge 2.9% + 30¢?+
Because it became the reference price. PayPal used that structure for online payments, Stripe launched in 2011 with the same headline figure, and once two widely-used providers advertised it, every new entrant was compared against it. Pricing at the reference point is easier to sell than explaining why you differ.
Is 2.9% + 30¢ based on actual costs?+
Only loosely. It has to cover interchange, network assessments, fraud, chargebacks and margin, and interchange alone is typically 1.5–2.1% on a domestic consumer card. But the exact figure is a round, memorable number rather than a calculated one — and it has stayed put while underlying costs moved.
Has the standard rate ever changed?+
The headline has been remarkably stable for well over a decade, even though regulated debit interchange was capped in the US in 2011 and interchange schedules are revised twice a year. Providers have generally competed on product rather than by moving the reference number.
Is 2.9% + 30¢ a good rate?+
It is the default, which is not the same thing. Whether it is good depends entirely on your average transaction size — at a $10 ticket it works out at 5.9%, and at $250 it is 3.02%. Compare on effective rate rather than on the headline.