Card security code

The CSC for American Express is a four-digit code on the front of the card above the account number.

CSC was originally developed in the UK as an eleven-character alphanumeric code by Equifax employee Michael Stone in 1995.

After testing with the Littlewoods Home Shopping group and NatWest bank, the concept was adopted by the UK Association for Payment Clearing Services (APACS) and streamlined to the three-digit code known today.

The card security code is not encoded on the magnetic stripe but is printed flat.

Virtual terminals and payment gateways do not store the CVV2 code; therefore, employees and customer service representatives with access to these web-based payment interfaces, who otherwise have access to complete card numbers, expiration dates, and other information, still lack the CVV2 code.

Supplying the CSC code in a transaction is intended to verify that the customer has the card in their possession.

The card security code is located on the back of Mastercard , Visa , Discover , Diners Club , and JCB credit or debit cards and is typically a separate group of three digits to the right of the signature strip
On American Express cards, the card security code is a printed, not embossed, group of four digits on the front towards the right