# Checking with Address Verification Service {#en_PP_avs .concept}

An article about the procedure of verifying customers' postal codes and addresses for processing American Express, Mastercard, and Visa payments via Payment Page.

## General information {#section_ofb_dcx_ydb .section}

**Address Verification Service** \(AVS\) is a service that allows you to check whether a customer who makes a payment by a bank card is the actual cardholder. The AVS check is performed by matching the address specified by a customer while performing a payment with the cardholder address according to the bank card Issuer.

AVS verification is mandatory for payments with Visa and Mastercard cards performed in the UK, and optional in the USA, Australia, Canada and New Zealand. For American Express, AVS verification is mandatory in the USA and Canada and optional in other countries.Therefore, it may be required additional mandatory parameters in the request for payment: the postal code `avs_post_code` and the address `avs_street_address` of a customer, for more information, see [Submission of additional payment information](en_pp_clarification.md). If the data does not passed, not pass validation or empty, you receive the appropriate decline code and message. The result of the AVS check is sent in the callback parameter `avs_result`.

**Note:** The requirement to provide AVS parameters persists even if the payment is made by a token or a saved bank card.

## Results of checking with AVS {#section_gq3_n12_pfb .section}

Possible codes with additional information and descriptions can be found below.

|Code|Additional information|Description|
|----|----------------------|-----------|
|W, Z|Partial match|Post code matches, but street address does not|
|A|Partial match|Street address matches, but post code does not|
|X, Y|Exact match|Address and post code match|
|N|No match|Street address and post code do not match|
|S, U|Address information unavailable.|Address information is unavailable for this account or an issuing bank does not support the AVS|
|R|System unavailable|System is unavailable at the moment, retry|

|VISA|A, N, R, U, Y, Z|
|MasterCard|A, N, R, S, U, W, X, Y, Z|
|American Express|A, N, R, S, U, Y, Z|

**Parent topic:**[Auxiliary procedures and additional capabilities](en_PP_Additional.md)