Interchange-Plus vs. Tiered vs. Flat-Rate Pricing: Which Costs You More?

Short answer: credit card processing pricing comes in five common models. Interchange-plus passes the card networks' cost through and adds a fixed, visible markup. Subscription pricing passes cost through and charges a monthly fee plus a small per-transaction fee. Tiered pricing sorts transactions into qualified, mid-qualified and non-qualified buckets set by the processor. Flat-rate pricing charges one percentage on everything. Enhanced recover reduced (ERR) pricing bills a low rate and then bills back the difference later. Only the two pass-through models let you see your markup; the other three blend it into the rate.

Every model on this list can be priced fairly, and every one can be priced badly. What differs is whether you can tell which one you have. That is the real argument for choosing a pricing model, and it matters more than whichever rate a salesperson quotes on the day.

Interchange-plus pricing

Interchange-plus, also called cost-plus or pass-through pricing, bills each transaction at its actual interchange rate and network assessments, then adds the processor's markup as a separate percentage and a per-transaction fee. A statement on this model shows interchange by card type, assessments as their own lines, and the markup as a fixed number that does not move when the card mix does.

The advantage is not that it is always cheapest. It is that the markup is visible, so it can be compared, negotiated and monitored. If your processor raises it, the statement shows the change. That is why interchange-plus is the pricing model most auditors prefer, and why auditing a merchant services statement is straightforward on it and difficult on anything else.

What to check on interchange-plus

• Whether the markup on the statement matches the markup in your pricing schedule.
• Whether assessments are billed at the networks' published amounts or inflated under similar names.
• Whether extra monthly and annual fees have appeared that were not part of the quote. A low markup with a long list of junk fees is not a low price.

Subscription or membership pricing

A variant of pass-through pricing: interchange and assessments at cost, a flat monthly subscription, and a small per-transaction fee instead of a percentage markup. Because the processor's income no longer scales with ticket size, it suits businesses with larger average transactions. The audit questions are the same as interchange-plus, plus whether the monthly fee is still the one you signed up for.

Tiered pricing: qualified, mid-qualified and non-qualified

Tiered pricing groups transactions into buckets, usually called qualified, mid-qualified and non-qualified, each with its own rate. The processor decides which interchange categories fall into which bucket, and the definitions live in the processor's terms rather than in the card networks' rules.

The problem is structural. The quoted qualified rate is often low, and many transactions do not land in it: rewards cards, business cards, keyed-in payments and online orders frequently fall into the more expensive buckets. The gap between what a transaction cost the processor and the bucket rate you paid is invisible, so the markup cannot be seen, compared or monitored. Tiered pricing is not always more expensive. It is always harder to audit, and over time that tends to amount to the same thing.

How to check a tiered statement

Calculate your effective rate (total processing fees divided by total card volume) and track it month to month. Then look at the share of volume billed as mid-qualified and non-qualified. If that share is large or rising while your business has not changed, the bucket definitions are doing the work. The benchmark question is what the same transactions would have cost on interchange-plus with a fair markup; see What Is a Good Effective Rate for Card Processing?

Flat-rate pricing

Flat-rate processing charges one percentage, often with a per-transaction fee, on every card regardless of type. It is the model used by most payment facilitators and all-in-one point-of-sale providers, and its appeal is simplicity: the cost of a sale is predictable before the card is swiped.

The trade-off is that the flat rate has to cover the most expensive cards you accept, so on cheaper transactions, such as regulated debit cards, you pay well above the underlying cost. For a small or new business, simplicity can be worth that. As volume grows, the difference between a flat rate and pass-through pricing on the same card mix grows with it, and flat-rate providers rarely lower the rate unless asked.

ERR and bill-back pricing

Enhanced recover reduced (ERR) pricing, also called bill-back pricing, is the hardest model to read. Each transaction is first billed at a low qualified rate. Transactions that did not qualify are then charged a surcharge on a later statement, often the following month, calculated from the difference between the rate you were charged and the processor's rate for that transaction type.

Because the extra charge arrives a month late, a single statement never shows the full cost of that month's sales. Reconciling it means matching each statement's surcharges back to the prior month's volume. If your statement has lines describing non-qualified surcharges, bill-backs or downgrades applied to a previous period, you are on this model, whatever the contract called it.

How to tell which pricing model you are on

• Interchange-plus: many interchange lines by card category, assessments listed separately, one consistent markup.
• Subscription: interchange at cost plus a named monthly membership or subscription fee.
• Tiered: volume summarized under qualified, mid-qualified and non-qualified, each with its own rate.
• Flat rate: one percentage applied to all volume, with no interchange detail at all.
• ERR or bill-back: a low rate on this month's sales, plus surcharges referring to last month's.

Which credit card pricing model is best?

For most established businesses, a pass-through model, interchange-plus or subscription, is the one that can be verified, which is why it is usually the right answer. Flat rate is reasonable at low volume when simplicity matters more than the last fraction of a percent. Tiered and bill-back pricing are the two to move away from, not because they must be expensive, but because nobody, including you, can tell whether they are.

AIME reads processing statements on any of these models, in any format, from 30 days to 36 months of history. It benchmarks every line against fair market rates and your contracted rates, and flags hidden markups and junk fees, with an AIME consultant supporting the conversation with your processor. There is no switching and no integration, and if nothing is found there is no fee. You can run an audit here.

Frequently asked questions

What is interchange-plus pricing?

Interchange-plus pricing charges each card transaction at its actual interchange and network assessment cost, plus a fixed processor markup shown separately on the statement. It is the most transparent common model for credit card processing.

Is tiered pricing bad?

Not always more expensive, but always hard to audit. The processor decides which transactions are qualified, mid-qualified or non-qualified, so the markup inside each rate cannot be seen or compared.

Is flat-rate processing more expensive than interchange-plus?

Often, as volume grows. A flat rate has to cover the most expensive cards you accept, so lower-cost transactions such as debit are billed well above their underlying cost. At low volume the simplicity can be worth it.

What is ERR pricing on a merchant statement?

Enhanced recover reduced, or bill-back, pricing charges a low rate up front and adds surcharges for non-qualified transactions on a later statement. It makes the true monthly cost difficult to see without reconciling two statements together.

Can I switch from tiered to interchange-plus with my current processor?

Often, yes. Many processors offer interchange-plus on request, especially to established accounts. Ask in writing, confirm the markup and every monthly fee in the new schedule, and check that the change does not restart your contract term; see Merchant Processing Agreements.