Protecting your credit card numbers has become more challenging as identity thieves and scam artists develop new methods to obtain your information. Credit card CV numbers appear on credit cards as an additional security measure to protect against unauthorized use. The CV number is provided by the credit card issuer and is printed directly on the card. As long as you keep the card safely in your possession and your CV number private, scam artists should not be able to use your card number to make unauthorized charges.
TL;DR (Too Long; Didn't Read)
A credit card's CV number is provided for added security and it is typically located on the back of the card by the signature block.
Location of the CV Number
Three of the four major credit card companies — Visa, Mastercard and Discover — use a three-digit CV number. It is printed on the back of the card, to the right of the 16-digit account number in the signature strip. American Express uses a four-digit CV number, which is printed on the front of the card immediately after the embossed credit card number. The CV number does not appear on any other documents related to the account.
Purpose of CV Numbers
As the use of credit cards for phone and internet purchases increased, the credit card industry recognized the need to better protect shoppers against unauthorized use of their cards. The CV number, also known as the card verification value or card verification code, was developed to offer enhanced security against identity thieves or credit card scam artists.
Major card issuers now include these three- or four-digit codes on all their credit cards, creating a combination of card number and CV code unique to each cardholder.
How the CV Number Works
The CV number is not encoded or included in the magnetic strip with your number, so it cannot be obtained by skimmer devices used by thieves to remotely learn your credit card number. The CV number also does not appear on any of your bills or credit card statements, so it cannot be accessed from those documents even if a thief gets access to them.
In theory, then, only the card owner and authorized user can use the card to make online or other "card-not-present" transactions. The CV number in effect identifies you to online or phone merchants as the authorized user of the credit card number being used for a purchase.
Protect Your CV Number
To maximize its effectiveness, do not share your CV number with anyone else. Do not allow the card out of your possession, because this might give someone the opportunity to copy the card number and CV number together. He could then use these for online or phone purchases.
If you choose to scratch the CV number off the card so no one can read it, be sure you have it memorized or record it somewhere safe so you can still use it. The CV number is not the same as your PIN number, which is a 4-digit personal identification code used when accessing ATM machines.
As a national security analyst for the U.S. government, Molly Thompson wrote extensively for classified USG publications. Thompson established and runs a strategic analysis company, is a professional genealogist and participates in numerous community organizations.Thompson holds degrees from Wellesley and Georgetown in psychology, political science and international relations.