How to run a year-end chargeback review

A year-end chargeback review should rebuild your ratio the way Visa and Mastercard calculate it, tally disputes by reason code, and total the fees you paid. Holiday disputes keep arriving into spring, so December figures describe an unfinished year; repeat the count in spring.

Why is a December review incomplete?

Holiday disputes finish months after the holidays. Stripe says cardholders typically have 120 days to dispute, merchants usually get 7 to 21 days to respond, and issuers take 60 to 75 days to decide.

A charge made on Black Friday can be disputed in March and decided in May. The figures that matter most for next spring are still forming in December. Treat the review as a snapshot and plan to repeat the count after the holiday disputes have landed.

How do Visa and Mastercard calculate your ratio?

Each network uses its own formula, and a dashboard that divides disputes by orders placed can understate the Visa number. Rebuilding both is the most useful December task.

Visa's VAMP (the Visa Acquirer Monitoring Program) divides fraud reports (TC40) plus disputes (TC15) by settled transactions (TC05) for card-not-present sales. Since 1 April 2026, a merchant in the US, Canada, the EU or Asia Pacific has been classed as excessive at 150 basis points, but only if it also logs at least 1,500 such events in the month. Stripe adds that a transaction in both reports counts twice, and that refunds and dispute outcomes do not reduce the count.

Mastercard's Excessive Chargeback Merchant band starts at 100 chargebacks and a ratio of 1.5%, running to 299 chargebacks and 2.99%. Its ratio divides chargebacks received this month by captured payments from the previous month. A surge of November sales sits in the denominator of December's ratio, and January's lower sales sit in February's, so check your own months against this rule and not the processor's headline number.

What do your reason codes tell you?

Each reason code points to a different fix. A reason code is the label the card network puts on a dispute to say what the customer is claiming.

• Credit-not-processed disputes point at refund speed.
• Not-received disputes point at carrier choice or ship dates.
• Fraud codes point at checkout controls.

The total count does not say which of these is the problem. Tally each code separately for September through December.

Read results by code with care, because samples are small. Stripe publishes a win-likelihood scale that runs from 60% at 5 dots to 5% at 1 dot, which shows how much outcomes can differ between cases. A seller with 12 disputes in a code cannot draw much from a 50% result, so ask instead whether each lost case lacked a record you could have kept.

What did disputes cost you in fees?

Add up every fee, won or lost, answered or ignored. On Stripe in the US, the dispute received fee is $15 and is not refunded. A further $15 countered fee, charged on disputes initiated after 17 June 2025, comes back if you win.

Shopify charges a $15 US chargeback fee that is returned on a win. Fees on cases you answered and lost belong in the same total as fees on cases you never answered. Set that sum against the hours spent, and compare processors with the dispute fee comparison for 2026.

Reserves belong in the review too. Shopify describes a reserve as a hold on part or all of your funds against chargeback and refund losses, with examples of $1,000 fixed for 120 days or 10% of payouts for 120 days. Check whether a reserve is in place on your account.

Takeaway: what to do this week

1. Rebuild the Visa ratio. Count TC40 and TC15 events against settled card-not-present transactions, and check against 150 basis points and 1,500 events.
2. Rebuild the Mastercard ratio. Divide each month's chargebacks by the previous month's captured payments, and compare with 100 chargebacks and 1.5%.
3. Tally disputes by reason code. Use September to December, then fix the matching cause: refund speed, ship dates or carriers, or checkout controls.
4. Total the fees. Include lost and unanswered cases, and make any changes before the next holiday window opens.

Sources: Visa, "Acquirer Monitoring Program fact sheet 2025", PDF dated 14 May 2025; Stripe Docs, "Dispute and fraud card monitoring programs"; Stripe Support, "June 2025 pricing updates for disputes", effective 17 June 2025; Stripe Docs, "Dispute evidence best practices"; Stripe Docs, "How disputes work"; Shopify Help Center, "Reserves"; Shopify Help Center, "Responding to chargebacks". All checked 24 October 2026.