Reason code categories, response deadlines, and what Visa's VAMP program actually measures — the practical version, not the 40-page operating regulations.
Visa organizes disputes into four numbered categories. The first digit of the reason code tells you immediately which category you're dealing with — and which kind of evidence will actually matter.
| Category | Code Range | Covers | Example Codes |
|---|---|---|---|
| Fraud | 10.x | Transactions the cardholder says they never authorized | 10.1 Counterfeit fraud · 10.4 Card-absent fraud |
| Authorization | 11.x | Transactions processed without proper authorization | 11.2 Declined authorization · 11.3 No authorization |
| Processing Errors | 12.x | Merchant-side processing mistakes | 12.1 Late presentment · 12.5 Incorrect amount · 12.6 Duplicate processing |
| Consumer Disputes | 13.x | Disputes over the goods, service, or transaction itself | 13.1 Merchandise not received · 13.3 Not as described · 13.6 Credit not processed |
Merchants get a uniform 30 days to respond at each phase of a Visa dispute, starting the day after Visa initiates that phase. Cardholders, on the other hand, typically have up to 120 days from the transaction or expected delivery date to file — and up to 540 days for certain reason codes.
Visa retired its older Visa Dispute Monitoring Program (VDMP) and Visa Fraud Monitoring Program (VFMP) in favor of VAMP, a single combined risk score. VAMP enforcement began October 1, 2025, and shifts the emphasis from flagging individual merchants toward monitoring risk at the acquirer-portfolio level — meaning your bank or processor now has direct visibility into your dispute activity as part of their own risk exposure.
| Classification | Threshold | Minimum Volume |
|---|---|---|
| Merchant — Excessive (most regions) | 1.5% | 1,500 combined TC40/TC15 records |
| Merchant — Excessive (CEMEA region) | 2.2% | 1,500 combined TC40/TC15 records |
| Acquirer — Above Standard | 0.5%–0.7% | 1,500 combined TC40/TC15 records |
| Acquirer — Excessive | ≥0.7% | 1,500 combined TC40/TC15 records |
Thresholds shown reflect the revised figures effective April 2026. The VAMP ratio is calculated as (fraud reports + disputes) ÷ total transaction count; a related "enumeration ratio" separately tracks card-testing style attacks.
Mastercard groups its reason codes into four functional categories, simplified in its 2016 reason-code overhaul.
| Category | Focus | Example Codes |
|---|---|---|
| Authorization-Related | Errors in the authorization request | 4808 |
| Point-of-Interaction Error | Processing errors during the transaction | 4834 |
| Cardholder Dispute | Challenges to goods, services, or transaction terms | 4853, 4854 |
| Fraud-Related | Unauthorized or fraudulent activity | 4837, 4849, 4870, 4871 |
Mastercard gives merchants a consistent 45 calendar days to submit representment documentation through their acquirer's dispute platform. Issuers and cardholders generally have 90–120 days to file the original dispute, depending on the specific reason code.
