SMMP, Mastercard’s Scam Merchant Monitoring Program, is the network’s mechanism for identifying and cutting off merchants running scams, enforceable from 24 Jul 2026 in every market except Jordan. When a trigger fires, the acquirer or payfac must open an investigation within 72 hours. The triggers fall into two groups. Every merchant is watched for an authorization approval collapse (at least 25 transactions in 72 hours with the approval rate dropping 50 points or more, or falling below 30%), a GRIP letter from Mastercard linking the account to suspected scam activity, or an alert from an approved Merchant Monitoring Service Provider (MMSP). Merchants with six months or less of Mastercard history carry three extra triggers, one of which is a combined refund and chargeback rate above five percent over a rolling 30 day window with at least 500 transactions. That five percent figure is a new merchant signal, not the universal threshold.
At a glance
- Effective 24 Jul 2026, every market except Jordan
- Investigation opened within 72 hours of a trigger
- All merchants: authorization rate collapse · GRIP letter · MMSP alert
- New merchants (6 months or less): fraud code 56 ×2 issuers · scam cited chargebacks ×2 issuers · or refunds plus chargebacks above 5% (500+ txns, rolling 30 days)
- Confirmed scam: immediate Mastercard and Maestro stop, possible MATCH listing
Why it matters
SMMP works nothing like the fine ladders of the Excessive Chargeback Program: there are no assessments, no remediation tiers and no appeal ladder. If the investigation concludes the merchant is a scam operation, Mastercard and Maestro acceptance stops immediately, with a MATCH listing a likely follow on. Two design choices deserve attention where the new merchant combined rate applies: refunds and chargebacks are counted together, so refunding aggressively to suppress disputes does not lower the number, and winning a representment does not remove the chargeback from the calculation. Subscription and trial merchants, whose refund plus dispute totals run structurally high, should track the combined rate per rolling window as a standing metric well before their six month mark. Visa is tightening in parallel: the VAMP threshold drop in April 2026 means high risk merchants now face stricter math on both networks at once.