There’s a security feature called a CVV, or card verification code, that the vendor will require in order to process the transaction. Here’s how to find your CVV and why it’s so important.

Because this security code is located only on your physical card, merchants may ask for the CVC when you pay online or over the phone to verify that you own the card.

The American Express card identification number — or CVV equivalent — is a four-digit code that can be found above the account number on the front of the credit card.