A low chargeback ratio may no longer mean your business is in the clear.
Starting April 1, 2027, Mastercard plans to combine reported fraud and non-fraud chargebacks under a redesigned Global Merchant Audit Program (GMAP). If your fraud and dispute teams work from separate dashboards, you may have a blind spot.
Why does this matter?
Fraud can count against you even when it never becomes a chargeback. Your chargeback ratio alone may no longer reflect your full risk exposure.
Two new merchant categories introduce significant financial consequences:
- High Dispute Merchant (HDM): Merchants meeting all three criteria (at least five cleared transactions, $5,000 USD in combined reported fraud and non-fraud chargebacks, and a ratio of 5% or more) may face assessments starting at $5,000 per month from month seven, rising to $10,000 per month from month 12 and $25,000 per month from month 19.
- Excessive Dispute Merchant (EDM): Merchants meeting the same transaction minimum, with at least $10,000 USD in combined reported fraud and non-fraud chargebacks and a ratio of 50% or more, may face assessments of $5,000 in month one, $25,000 in month two, $100,000 monthly from months three to 11, $200,000 monthly from month 12, and $300,000 monthly from month 19.
Merchants identified as EDMs for two months may also face fraud-related chargeback liability covering transactions from the preceding three months and the following six months.
Figures are based on details reported by payment providers and may change before launch.
Even merchants outside these new categories will feel it: Mastercard’s existing Excessive Chargeback Merchant threshold is reportedly dropping from 1.5% to 0.9% in stages between 2029 and 2031.
This isn’t simply another compliance change. It’s a shift in how payment networks assess merchant risk. You can be below today’s thresholds and still be unprepared for tomorrow’s rules.
What should businesses do now?
- Monitor fraud reports and chargebacks together.
- Identify risk patterns across processors, platforms, and internal teams.
- Ask your acquirer about its own monitoring thresholds, which may be stricter.
- Review reporting and risk controls well before April 2027.
At Cartis Payments, we help businesses assess their payment infrastructure, identify gaps in risk management and visibility, and prepare for changes like these.
Don’t wait for a monitoring notice to discover what your data has been telling you.
Contact Cartis Payments to discuss how to prepare your payment environment.