What Is a Signature Code on a Credit Card?
- A signature code on a credit card is a three to four-digit security code that prevents a thief from using a stolen credit card to make unauthorized purchases. Requiring a consumer to provide the code during Internet and over the phone transactions ensures that a consumer is in possession of a credit card at the time of a purchase.
- Major credit card brands such as MasterCard, Visa, Discover and American Express all print a signature code on their cards. Of the four major brands, American Express is the only brand to print a signature code on the front of a credit card. The code appears on the back of MasterCard, Visa and Discover cards.
- Signature codes are not printed on billing statements and do not appear on online credit accounts. This way, if a thief uses an old billing statement to obtain an account holder's credit card number and card expiration date, he cannot run up fraudulent charges over the Internet. He also cannot make in-store charges without being in possession of the original credit card.
- Even though a signature code appears immediately after -- or in close proximity to -- a credit card number, it is not an extension of a credit card number. In some instances, and for security reasons, a bank may only print the last four digits of a credit card number on the face of a card, in which case, the signature code is printed immediately after the last four digits.
