What is the primary function of the Address Verification Service (AVS)?

The primary function of the Address Verification Service (AVS) is to verify the card ownership address. AVS helps merchants and payment processors confirm that the billing address provided by a customer matches the address on file with the issuing bank for the credit card. This verification process is an important tool in reducing fraud by providing an additional layer of security during card-not-present transactions, such as online purchases. When a customer enters their address information during the checkout process, AVS checks that information against the issuing bank's records and provides feedback to the merchant about whether the addresses match. This verification can lead to more secure transactions and minimize the risk of chargebacks due to fraudulent activity.

In contrast, tracking customer purchase history is not a function of AVS; rather, this typically involves customer relationship management (CRM) systems. Similarly, authenticating the transaction amount does not fall under AVS's capabilities, as that is more related to the payment processing systems that validate the exact amounts being charged. Lastly, while preventing unauthorized access to accounts is critical in the payments industry, it is managed through various security protocols and technologies beyond what AVS specifically offers.