How to find your CVV2 number:
On a VISA, MasterCard, and Discover please turn your card over and look in the signature strip. You will find (either the entire 16-digit string of your card number, OR just the last 4 digits), followed by a space, followed by a 3-digit number. That 3-digit number is your CVV2 number. (See below)
On American Express Cards, the CVV2 number is a 4-digit number that appears above the end of your card number.

What is CVV2?
CVV2 is a security precaution that we must ask for on all credit card transactions. Since a CVV2 number is listed on your credit card, but is not stored anywhere, the only way to know the correct CVV2 number for your credit card is to physically have possession of the card itself. All VISA, MasterCard, Discover, and American Express cards made in America and in Europe in the past few years have a CVV2 or CV2 number.

Visa, MasterCard, & Discover:
This number is printed on your VISA, MasterCard, and Discover cards in the signature area of the back of the card. (it is the last 3 digits AFTER the credit card number in the signature area of the card). IF YOU CANNOT READ YOUR CVV2 NUMBER, YOU WILL HAVE TO CONTACT THE ISSUING BANK OR INSTITUTION.
American Express:
American Express cards show the CVV2 printed above and to the right of the imprinted card number on the front of the card.