What Is the CSC Security Code for a Credit Card?

The Credit Card Security Code (CSC) is a security feature designed to protect transactions made without the physical card present. This unique code helps verify the cardholder’s authenticity during purchases. It acts as an additional layer of defense against unauthorized use for online, phone, or mail orders. The code ensures the individual initiating the transaction has physical possession of the credit card.

Understanding Your Credit Card’s Security Code

A credit card security code is a unique three or four-digit number printed on a credit or debit card. Unlike the main card number, these codes are not embossed, making them unreadable by mechanical imprinters. Their primary purpose is to enhance security for “card-not-present” transactions, where the physical card is not swiped or inserted.

Different card networks use various acronyms for this security feature. Visa cards use CVV (Card Verification Value), Mastercard uses CVC (Card Validation Code), and American Express cards use CID (Card Identification Number). American Express codes are four digits, while others are three. This code is distinct from the card’s primary account number and the Personal Identification Number (PIN) used for ATM withdrawals or in-person debit transactions.

Locating the Security Code

The security code’s placement and length vary by card network. For Visa, Mastercard, and Discover cards, the three-digit security code is on the back of the card, usually within or to the right of the signature strip.

American Express cards feature a four-digit security code on the front of the card. It is usually printed above or to the right of the main card number. This distinction in length and location is a key characteristic of American Express cards.

The Role of the Security Code in Transactions

The credit card security code safeguards transactions, especially those conducted remotely where the physical card is not present. This code helps prevent fraud by confirming the person making the purchase possesses the physical card. When making an online or phone purchase, merchants request this code as an additional verification step, reducing the risk of unauthorized use if only the card number and expiration date are compromised.

Merchants are prohibited from storing the security code after a transaction is authorized. This rule, part of industry standards like the Payment Card Industry Data Security Standard (PCI DSS), means that even if a merchant’s database is breached, security codes cannot be stolen. This non-storage requirement helps ensure a stolen card number cannot be easily used for future fraudulent “card-not-present” transactions without the corresponding security code.

The security code differs from a PIN, which is primarily used for authenticating in-person transactions like ATM withdrawals or point-of-sale purchases. The security code’s purpose is to verify card possession during remote transactions, not to authenticate the cardholder’s identity through a secret numerical password. Maintaining the confidentiality of your security code is important. Never share it in unsolicited emails, texts, or suspicious phone calls, as legitimate entities will only request it during a transaction you initiate.