4 digits on front of card
Visa, Mastercard and Discover
Last 3 digits on back of card
The Card Security Code is the group of numbers immediately following your Visa, MasterCard, American Express and Discover credit card number. These numbers are used by your credit card company to help prevent fraud. This number is only used in processing your transaction and will not be recorded.
Note: The digits are printed on your card, rather then stamped in the plastic like the digits in your credit card number.