The Three-digit-code is the last three numbers on the back of a Visa card, and may appear in a white box to the right of the signature panel (as shown) or be printed on the signature panel of Visa cards (as shown).

• The Three-digit code is a crucial security feature on Visa cards that helps merchants validate purchases made with Visa cards.
• The CVV2 can also help prevent large scale "fraud attacks". E.g. "hacking" attacks and generation of card numbers.
• If a purchaser only has the 16-digit credit card number and the expiry date, they may not have actual physical possession of the card. By asking customers for the Three-digit code, you can verify that the person making the purchase has a genuine Visa card in hand.
• After submitting a request for authorization for the card information (account number, card expiration date, and Three-digit-code), you'll receive a response that lets you know whether the Three-digit-code is matched or mismatched.
• Regardless of the Three-digit-code verification response, if the issuer does not approve the authorization request, you should not complete the transaction.

If the merchant submits the Three-digit-code for authentication and the issuer does not participate in the validation, the merchant will be protected against liability for any potential fraudulent transactions.