What are Card Security Codes?

The card security code (CSC) is a 3 or 4 digit number that is not part of the credit card number.

The number appears only on the card itself (not on receipts or statements), so it provides some assurance that the physical card is in your possession. This helps us reduce fraud.

Visa
MasterCard
Discover
The CSC is the last 3 digits of the account number panel.
  

American Express

 
The CSC is a 4-digit number printed above and to the right of the account number.
The CSC is a 4-digit number printed above and to the left of the account number.