Amex's refund-failure code, decided on the merchant's refund records and the policy that governed the original sale.
Amex C02 is the refund-failure code. The cardmember acknowledges the purchase, acknowledges that a refund was agreed, and is now claiming the credit never reached their card. The merchant's defence is documentary: the refund record, the policy that governed the original sale, and the communication trail with the buyer.
How the dispute actually arrives
C02 notifications arrive within Amex's standard chargeback flow, with the cardmember's claim phrased as a missing refund. The merchant has 20 days from receipt to respond, the shortest window of any major network. C02 is the Amex parallel to Visa 13.6 (Credit Not Processed) and serves the same role in the dispute taxonomy.
What the issuer is looking for
Amex wants the refund transaction record. If the merchant processed the refund and Amex can match the credit to the cardmember's account, the dispute typically resolves at network level without further argument. If the refund was processed to a different account, a different card, a store credit, or in cash, the merchant must show that the alternative was agreed.
Where the refund was not processed at all, Amex wants to see why. A policy that disclosed a 30-day refund window which had not yet elapsed is a different argument than a policy that promised a same-week refund the merchant did not honour. The published refund policy the cardmember agreed to at checkout is the framing document.
Common scenarios merchants see
A physical-goods return where the merchant received the product but did not issue the credit. The shipping carrier's confirmation of the return and the inventory log are the supporting records, but Amex will side with the cardmember if the refund itself was not processed.
A cancelled service where the merchant promised a partial refund. The agreement matters more than the merchant's recollection. Written confirmation, whether email, support ticket, or account note, is the difference between a winnable case and an unwinnable one.
A partial refund the cardmember disputes as incomplete. The calculation is the case: the original transaction, the agreed cancellation fee or restocking charge, the refund issued, and the cardmember's signed or written agreement to the deduction.
What this code is not
C02 is not a non-receipt code, a not-as-described code, or a cancellation code. If the cardmember never received the goods, the dispute will arrive as C08. If the goods arrived but were defective, it will arrive as C31. Misreading C02 as a quality dispute, and submitting delivery or product evidence the issuer never asked for, is the most common loss pattern.
Where this fits in our service
Amex C02 letters are built from the merchant's refund records and the policy in force at the time of sale. We draft them when the merchant has the documentation; when the refund was simply missed, the honest path is usually to issue it and avoid the dispute. If you have just received one, you can start with a free first letter.
Official source: Amex rules. Last reviewed 2026-05-14.