Guide
When a SEPA debit comes back, it carries an ISO 20022 reason code. These are the ones shops see most often.
| Code | Meaning | What to do |
|---|---|---|
| MD06 | Refund requested by the payer | Contact the customer; offer a payment link. Within 8 weeks they don't need a reason. |
| AM04 | Insufficient funds | Retry later or send a payment link. |
| AC01 | Incorrect account number | Ask for correct bank details or another payment method. |
| AC04 | Account closed | Ask for new bank details. |
| AC06 | Account blocked | Send a payment link; don't retry automatically. |
| AG01 | Account doesn't allow Direct Debit | Ask for another account or payment method. |
| MD01 | No valid mandate | Stop debiting; request a new mandate. |
| MD07 | Account holder deceased | Stop debiting and handle with care. |
| MS02 | Refused by the payer, no reason given | Contact the customer before trying again. |
| MS03 | Refused by the bank, no reason given | Contact the customer; consider another method. |
| SL01 | Blocked by a service at the payer's bank | The payer may have blocked your creditor ID; ask them. |
Banks don't always use the most specific code. GoCardless passes on the code it receives.
A return happens before or around settlement — the debit never really succeeds. A refund (MD06) happens after a successful debit, when the payer asks their bank for the money back. Under SEPA Core, payers can request a refund of an authorised debit within 8 weeks, without giving a reason.
Account
Kalplex