Many worry about fraud. Most merchants require a debit or credit card number, expiration date, and security code to prevent fraudulent charges.

A card security code is a three- or four-digit number on the back of credit and debit cards that verifies transactions when the card is not present. The security code is on American Express® cards.

Essentially, a CSC is a feature that provides an additional layer of safety and security for shoppers, protects merchants from fraud and prevents chargebacks.

A cardholder must be in possession of their physical credit or debit card to find, check and enter the card’s CSC.

CSC numbers prevent credit card fraud. Payment card industry guidelines ban retailers from retaining CSC data.

Online shoppers are increasingly using credit and debit cards. Online businesses require card and CSC numbers for purchases.

Sometimes credit or debit card chargebacks can occur during purchases even when customers and merchants enter the correct CSC.

CSC numbers are also referred to as: CVC: Card verification code CVC2: Card verification code, second generation CID: Card identification number