How do scheme fee errors happen, and how do you find them?
Scheme fee errors happen because Visa and Mastercard bill hundreds of fee types, some on aggregates and months in arrears, from schedules that change often. The usual errors are fees billed on the wrong region or product, fees billed twice, and optional services billed after an opt-out. You find them by recalculating the invoice from your transactions.
What is a scheme fee error?
A scheme fee error is a charge on a Visa or Mastercard invoice that does not match what the scheme's fee rules and your agreement set for the transactions you actually processed. Scheme fees are paid by both issuers and acquirers, separately from interchange. UK and EU rules cap interchange, while scheme fees are not capped (Ryft).
Errors are hard to see because one transaction can carry many fees. Submissions to the Reserve Bank of Australia describe single transactions "incurring over a dozen scheme fees" and schemes with "up to 800 categories of fees, sometimes with conditional fees and tiering" (RBA summary of submissions, 2025). An error in one of those fees rarely changes the invoice total enough for anyone to notice.
How scheme fee errors happen
Scheme fee errors usually come from one of four mechanisms: fees calculated on aggregates that cannot be matched to transactions, fees assessed on the wrong region or card product, the same fee billed twice, and optional services that keep billing after you stopped using them. Each one has its own check, set out in the next section.
Non-transactional fees billed in arrears on aggregates
Non-transactional scheme fees arrive on monthly invoices one to two months after the activity and are calculated on aggregates, such as monthly counts or volumes, rather than per transaction (Adyen help). That breaks any simple match between an invoice line and the transactions behind it. An aggregate built from the wrong month, or from the wrong set of merchant IDs, produces a plausible number that is wrong.
Fees assessed on the wrong region or product
Many scheme fees depend on where the card was issued and where it was used, and on the card product. A domestic transaction assessed as cross-border, or a consumer card billed at a commercial card rate, pays a higher fee than it should. These errors repeat on every affected transaction until the classification is fixed, so they grow into recurring monthly amounts.
The same fee billed twice
A fee can be charged twice when a transaction is re-presented, when a refund triggers a second assessment, or when the same fee is passed through by an acquirer or sponsor and also billed directly. Duplicates are easy to miss on an aggregated invoice because the unit count looks close to normal.
Optional services billed after an opt-out
Schemes sell optional services, such as tokenisation and fraud tools, alongside the core fees. When a programme opts out or retires a product, the billing does not always stop. Nobody owns the line, so it keeps getting paid.
What regulators have found
Regulators in Australia and the UK have both recorded that scheme fees are hard to reconcile and that errors often go unrecovered. The Reserve Bank of Australia heard of fee schedules "often 400 pages long" and of billing errors that were "resource and time-intensive to investigate", with schemes that "did not proactively reimburse" acquirers (RBA summary of submissions, 2025).
The RBA's March 2026 conclusions record that some PSPs "absorb" fee inaccuracies rather than investigate them, because of complexity and frequent revisions, and that schemes charge PSPs for the reports needed to reconcile (RBA conclusions, March 2026). Scheme fee roadmaps with machine-readable invoices and error remediation are due by 1 April 2027.
In the UK, the Payment Systems Regulator found that core scheme and processing fees paid by acquirers rose by more than 25% in real terms between 2017 and 2023, costing UK businesses at least £170m a year (PSR final report, March 2025). Its July 2026 decision concluded that the schemes "do not give acquirers sufficiently clear and detailed information about their fees" and requires them to provide the fee logic needed to reconcile invoices to transactions from July 2027 (PSR PS26/1, July 2026). Our PSR remedies explainer covers the dates.
How to check your scheme invoices yourself
You can test a scheme invoice by rebuilding its largest lines from your own transaction data and the scheme's fee schedule. Start with the ten lines that cost the most, check each one's count and rate, then look for the three error patterns that recur: wrong classification, duplicates and services you no longer use.
Line up the invoice with the right month
Identify the activity month each line charges for. Non-transactional fees usually relate to one or two months earlier.
Rebuild the counts
For the ten largest lines, count the qualifying transactions or accounts in your own data, split by region, channel and card product, and compare with the billed units.
Check the rate against the schedule
Find the current rate in the scheme's fee schedule and the effective date of the last change. A notice applied before its effective date is an error.
Look for duplicates
Search for the same fee on the scheme invoice and on your acquirer or sponsor invoice, and for fees on re-presented or refunded transactions.
List services you pay for
Match every optional service line to a product you still run. Any line without an owner goes on the list to query.
Raise it with evidence
Send the scheme or your acquirer the fee, the transactions, the expected amount and the billed amount. The regulators' findings suggest refunds rarely arrive unasked.
How FeeVerify handles scheme fee errors
FeeVerify builds fee rules from your scheme agreements and processing agreements, recalculates every transaction against them, and compares the result with each scheme invoice line, including fees billed on aggregates. With optional continuous assurance it runs again on each new month of data, so an error introduced by a fee change is found in the month it starts.
Every finding carries the rule, the clause or schedule entry it comes from, the transaction rows and the amount, with a confidence grade. AI does the high-volume analysis and experienced payments specialists sign off each material finding before you raise it, so you need no new headcount. When the schemes start providing fee logic in the UK from July 2027, that data can be checked the same way. The how it works page shows the steps.
Sources: Ryft guide to European payment fees, 2026; RBA summary of submissions, 2025; RBA conclusions on scheme fees, March 2026; PSR final report, March 2025; PSR PS26/1, July 2026; Adyen help on non-transactional scheme fees.
Start with one month of your own data.
A pilot begins with the agreements that protect both sides, then your contracts and one month of settlement data, scoped with a payments specialist on the first call. The 30-day diagnostic re-costs every transaction against them and shows each variance with its clause, before any recurring fee.