Reason code · American Express
Amex A02: no valid authorization
A02 means the charge went through without a valid approval. The approval was declined, didn’t match the charge, or the card had expired. You answer with the approval record, proof the charge came before the card expired, or a refund.
What A02 means
A02 means Amex has no valid approval on file for the charge you submitted. Amex’s guide names three causes:
- The approval code you submitted wasn’t the one you received, for example digits transposed when keyed.
- The approval submitted was wrong or belonged to a different charge.
- The card was expired.
It also covers charges that were declined and pushed through anyway.
Who raised it
Like the other A codes, A02 is about authorization, not about whether the customer was happy. A charge can be perfectly legitimate and still lose here because the approval behind it doesn’t hold up.
Time limit
Amex’s guide gives Card Members (Amex’s word for cardholders) up to 120 days from the transaction date to dispute most charges. Processor guides list this code under the same 120 days.
Your side of the clock is short. Amex’s own guide tells merchants to respond within 20 days. If you accept Amex through a processor such as Stripe or Square, the processor sets its own date, often a shorter one. The due date on your notice is the one that counts.
What proof matters
Amex accepts proof that a valid approval was obtained for the full amount, or proof that a refund directly offsetting the charge already went through. For an expired or not-yet-valid card, Amex also accepts proof the charge was incurred before the expiration date or within the card’s valid dates. Transit contactless fares have their own separate rules.
Declined means declined
Amex’s guide is blunt about prevention: include a valid approval with every charge, and don’t submit if the approval was declined. Force-posting a declined card, or reusing an old approval code on a new charge, is how small businesses walk into A02 without noticing.
Card-on-file businesses feel this most. A customer’s card expires, the stored number keeps getting billed, and the approval that would have caught it never happened.
The common mistake
Arguing that the customer owes the money. They may well owe it. A02 doesn’t ask that question. It asks for the approval, and an invoice can’t stand in for one.
Dispute Daddy builds this for you
Upload the notice and your records. Dispute Daddy builds a response around the reason Amex actually gave, and you approve it before you submit. See how the method works.
