Card scheme reason codes are the identifiers Visa, Mastercard and other card networks assign to a dispute, recording why the cardholder is asking for their money back. The code determines what evidence a merchant must supply, and how long they have to supply it.

Each network keeps its own reason code list, and the codes split into four broad families: fraud, where the cardholder says they never authorised the transaction; authorisation, where the transaction breached the network's approval rules; processing errors, such as duplicate charges or an incorrect amount; and consumer disputes, covering goods not received, goods not as described, or a cancelled subscription. A reason code is not a precise diagnosis: the issuer assigns it, not the merchant, and often gets it wrong.

See how to automate disputes with AI for how reason-code triage fits into the wider dispute workflow.

Frequently asked questions

Who assigns the reason code on a card dispute?

The card issuer assigns the reason code when the cardholder raises a dispute, not the merchant and not the acquirer. The code is often imprecise: a cardholder who has simply forgotten about a subscription can end up filed under fraud rather than a billing dispute, which changes what evidence the merchant has to supply to win the case.

Why does the reason code set the merchant's response deadline?

Each reason code family carries its own evidence requirements and response window, set by the card network rather than the merchant. A dispute answered with the wrong kind of evidence can lose even when the original transaction was entirely legitimate, which is why disputes teams spend so much of their time correctly classifying a case before they start building the response.

Are reason codes the same across Visa, Mastercard and other networks?

No. Each card network maintains its own list of reason codes, and the same underlying complaint, such as a duplicate charge, can carry a different code and a different evidence requirement depending on which network issued the card. Merchants processing cards across multiple networks need a mapping for each network rather than one shared playbook.