What is a CSC?
The Card Security Code (CSC), sometimes called Card Verification Value (CID), is a security feature for credit or debit card transactions, giving increased protection against credit card fraud. For Visa and MasterCard, the 3-digit CID code is located on the back of your card to the right of your card number. For American Express, the 4-digit code is located on the front of your card above the card number (see samples below).


American Express