What Is the CID on a Credit Card?

The credit card identification number (CID) is a security feature designed to protect consumers during transactions. It serves as a verification tool, primarily in situations where the physical card is not presented, such as online purchases or telephone orders. Understanding its role helps cardholders safeguard financial information and adds a layer of defense against unauthorized use.

Understanding the CID

The CID is a security code on your credit card, also known by several other names depending on the card network. These include Card Verification Value (CVV), Card Verification Code (CVC), Card Security Code (CSC), or CVV2 and CVC2. The primary purpose of this code is to verify that the individual making a purchase is the legitimate cardholder, especially in “card-not-present” scenarios.

This distinct three or four-digit number authenticates transactions conducted remotely. When you make a purchase over the internet or by phone, the merchant requests this code to confirm that you possess the physical card. It helps prevent fraudulent activity by ensuring the card is in the hands of the authorized user.

Locating Your CID

The location and number of digits for the CID vary depending on the credit card brand. For Visa, Mastercard, and Discover cards, the CID is a three-digit number. You will find this code on the back of the card, usually within or just above the signature strip, often as the last three digits in a series of numbers printed in that area.

American Express cards have a four-digit CID. This code is located on the front of the card, printed above or to the right of the embossed (raised) card number. Unlike the card number, the CID on American Express cards is not embossed.

The Security Role of the CID

The CID plays an important role in preventing credit card fraud, particularly in transactions where the physical card is not present. Unlike the primary account number and expiration date, the CID is designed not to be stored by merchants after a transaction is completed. This restriction is a security measure mandated by the Payment Card Industry Data Security Standard (PCI DSS).

This non-storage rule means that even if a merchant’s database is compromised, the stolen card numbers cannot be used for online or phone purchases without the corresponding CID. By requiring the CID for card-not-present transactions, businesses ensure that the person making the purchase has physical possession of the card. This reduces the risk of unauthorized transactions stemming from stolen card data. The CID serves as an authentication factor, verifying the card’s legitimacy and the cardholder’s presence during remote purchases.

Safeguarding Your CID

Protecting your CID helps prevent credit card fraud. Never share your CID through unsecured communication channels, such as standard email or text messages. These unencrypted methods can expose your financial information to unauthorized individuals. If you need to provide your CID over the phone, ensure you are in a private setting where others cannot overhear the information.

When making online purchases, always verify website security before entering your CID; look for “https://” and a padlock icon in your browser’s address bar, indicating a secure, encrypted connection. Be cautious of unsolicited calls, emails, or messages asking for your CID, as these could be phishing attempts. Merchants are prohibited from storing your CID after a transaction, so be wary if a website or service asks to save it for future use. Avoid writing down your CID or storing it in an easily accessible location.