In return of a credit card transaction, there will returned a 2-digit response code which is grossly standadized.
If you manage an ecommerce, these codes are useful and important because you can understand why a customer is not able to pay.
Most common code as follow:
| 00 | Approval |
| 01 | Declined - Call Issuer |
| 04 | Declined - Pick Up Card |
| 05 | Declined - Do Not Honor |
| 12 | Declined - Invalid Transaction |
| 13 | Declined - Card Amount Invalid |
| 14 | Declined - Card Number Invalid |
| 15 | Declined - No Such Issuer |
| 19 | Declined - Re-Enter |
| 51 | Declined - Insufficient Funds |
| 54 | Declined - Card Expired |
| 57 | Declined - Service Not Allowed |
| 61 | Declined - Customer Exceeds Withdrawal Limit |
| 62 | Declined - Restricted SIC Code |
| 63 | Declined - Restricted |
| 65 | Declined - Customer Exceeds Activity Limit |
| 78 | Declined - No Account |
| 85 | Approval |
| 97 | Declined - CVV MisMatch |
