# Address Verification Service (AVS) Check
**What does AVS stands for?**
AVS is a fraud prevention tool used to verify the address provided by a customer during a transaction. It compares the billing address entered by the cardholder with the address on file at the card-issuing bank. AVS is commonly used in card-not-present (CNP) transactions like online to reduce the risk of fraud.
**How does AVS works?**
When a customer enters their billing address during a transaction, the payment processor sends this information to the card issuer for verification. The card issuer checks the street address and ZIP code against the information they have on file. Based on the match (or lack thereof), the transaction can either approved, or declined.
**AVS response codes**
AVS response codes indicate how closely the entered billing address matches the one on file. These codes, which vary from network to network, tell the business what next steps they should take with the transaction. Following are the possible AVS response codes
| **AVS Response Code** | **Definition** |
| --------------------- | -------------- |
| **AVS Response Code** | **Definition** |
| --------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| A | Address matches - ZIP Code does not match |
| B | Street address match, Postal code in wrong format (international issuer)
Important: No longer used by Visa – expect AVS Response ‘A’.
|
| C | Street address and postal code in wrong formats
Important: No longer used by Visa – expect AVS Response ‘R’.
|
| D | Street address and postal code match (international issuer).
Important: No longer used by Visa – expect AVS Response ‘Z’.
|
| E | AVS Error |
| F | Address does compare and five-digit ZIP code does compare (UK only).
Important: No longer used by Visa – expect AVS Response ‘Z’.
|
| G | Service not supported by non-US issuer
Important: No longer used by Visa – expect AVS Response ‘R’.
|
| I | Address information not verified by international issuer
Important: No longer used by Visa – expect AVS Response ‘R’.
|
| M | Street Address and Postal code match (international issuer).
Important: No longer used by Visa – expect AVS Response ‘Z’.
|
| N | No Match on Address (Street) or ZIP |
| O | No Response sent |
| P | Postal codes match, Street address not verified due to incompatible formats.
Important: No longer used by Visa – expect AVS Response ‘Z’.
|
| R | Retry, System unavailable or Timed out |
| S | Service not supported by issuer.
Important: No longer used by Visa – expect AVS Response ‘U’.
|
| U | Address information is unavailable |
| W | 9-digit ZIP matches, Address (Street) does not match.
Important: No longer used by Visa – expect AVS Response ‘Z’.
|
| X | Exact AVS Match.
Important: No longer used by Visa – expect AVS Response ‘Z’.
|
| Y | Address (Street) and 5-digit ZIP match.
Important: No longer used by Visa – expect AVS Response ‘Z’.
|
| Z | 5-digit ZIP matches, Address (Street) does not match |
**What happens if the AVS system is down?**
If the AVS system is unavailable, the card issuer may return a response code indicating that AVS data could not be verified (such as code "R" for retry). Merchants can choose to proceed with or decline the transaction based on their risk appetite.
**How to start using AVS?**
Please contact the PayEngine Customer Success team to enable AVS checks. They will assist you in configuring to meet your specific requirements, including how to handle transaction approvals or declines based on each AVS response code
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