CVV CODE For your safety and security, our card processing server requires that you enter your card verification number, if one is available. The verification number is a 3 or 4 digit number printed on your card. If you are using a Visa, Mastercard, or Discover card, it is a 3 digit number that appears to the right of your card number (see below). If you are using an American Express card, the verification number is a 4 digit number that appears on the front of your card, above and either on the left or right of the card number (see below). If your card does not have a verification number, try another card or enter the number 000.