What Is a Signature Code on a Credit Card?

What Is a Signature Code on a Credit Card?
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When you buy something over the phone or online, the merchant asks you for the signature code on the credit or debit card you use for your purchase. A signature code is a three or four digit number printed on the card. You aren't asked for the signature code when shopping in person because the store's card scanner reads it electronically along with the rest of your account information.


The Function of Signature Codes

The credit card signature code is a security feature. When you provide the code, the merchant transmits it to the credit card issuer. The code shows that you have possession of the physical card. If the code is validated, your transaction goes through. Otherwise it is canceled. This feature helps prevent fraud because someone who gets your account number can't use it without the signature code. Essentially, a signature code serves as a substitute for your signature when you shop by phone or online.


Locating the Signature Code

If you have a Discover, MasterCard or Visa credit or debit card, look on the back of the card. The signature code is a three digit number printed on the same line where you sign the card on the extreme right. Only the last three numerals are the code, so ignore any digits preceding them. American Express uses a four digit signature code. Look on the front of the card on the right-hand side just above the account number.

Other Names for Signature Codes

Signature codes are also called security codes, verification codes and v-codes. A shopping website may indicate where to enter the code by referring to it with an acronym. Here's some common signature code abbreviations:


  • SPC: Signature panel code
  • CVD: Card verification data
  • CvN: Card verification number
  • CSC: Card security code
  • CVC or CVC2: Card verification code
  • CVV or CVV2: Card verification value
  • CVVC: Card verification value code