Pricing Model

Flat-Rate Pricing Explained

Flat-rate pricing uses a predefined pricing schedule that may combine a percentage with a fixed per-transaction fee. Rates can vary by payment channel, transaction category, provider, and merchant agreement.

Last reviewed: October 15, 2026 · Editorial policy

Quick Answer

Flat-rate pricing bundles interchange, assessment fees, and processor markup into a predefined pricing schedule that may include a percentage and a fixed fee. The applicable rate depends on the payment channel, transaction category, provider, and merchant agreement. It can simplify cost estimates, but does not pass through lower underlying interchange costs on individual transactions.

How Flat-Rate Pricing Works

Every card transaction involves interchange (paid to the issuing bank), assessment fees (paid to the card network), and processor markup. For transactions within a stated pricing category, flat-rate pricing bundles these costs into the applicable percentage and any fixed per-transaction fee.

The bundled rate is designed to be profitable for the processor across a typical card mix — meaning the processor earns more margin when customers use low-interchange debit cards and less when they use high-interchange premium reward cards. The merchant pays the applicable agreed rate for that transaction category rather than the underlying interchange item by item.

Providers may publish different rates for in-person, keyed, and online transactions. Compare the applicable channel and transaction category, including additional fees and any negotiated terms, rather than assuming in-person is always cheaper.

Hypothetical ticket-size illustration, not a provider quote: At 2.6% + $0.10 per transaction, a $5 transaction costs $0.23 (4.6%), while a $100 transaction costs $2.70 (2.7%). The fixed $0.10 component weighs more heavily on smaller tickets.

When Flat-Rate May Work Well

Very new businesses that want simple, predictable billing without learning interchange categories

Low-volume merchants where the per-transaction economics of interchange-plus don't justify complexity

Businesses with a mix of card types where a blended flat rate is competitive with actual interchange costs

Merchants who want to avoid monthly fees or long-term contracts common with some interchange-plus providers

Businesses that find the provider's pricing and agreement suitable after confirming eligibility and documentation requirements

When It May Not Fit

Higher-volume merchants where even a small difference in effective rate represents meaningful cost

Businesses with a card mix heavy in debit or basic credit, which carry lower interchange — you don't benefit from those savings under flat-rate

Merchants who want to audit processor charges separately from interchange costs

B2B merchants whose required corporate-card treatment is not covered by the provider's product or agreement

Advantages

Defined rates for applicable transaction categories make billing easier to understand
No need to understand interchange categories or card types
Often no monthly fees or long-term contracts
Simple fee calculations for transactions within the applicable pricing category

Trade-offs

You don't benefit when customers use lower-cost debit or basic credit cards
Harder to benchmark processor costs against alternatives
May have higher effective rate than interchange-plus for some card mixes
Some providers offer limited pricing transparency or customization

Common Misconceptions

❌ Myth: Flat-rate pricing is always more expensive than interchange-plus.

✅ Fact: Not necessarily. For merchants whose customers frequently use premium rewards cards (which carry high interchange), the flat rate may be close to or even lower than interchange-plus with a comparable markup. The only reliable comparison is calculating effective rate using your actual card mix.

❌ Myth: Flat-rate providers don't charge separate fees.

✅ Fact: Most flat-rate providers still charge for chargebacks, ACH refunds, hardware, and international card transactions at different rates. 'Flat rate' refers to the base transaction rate — other fees still apply.