SECURITY007 — Card Security Code Overview (CSC/CVV Code)

Last updated: September 1, 2026

he card security code (CSC) is a short numeric code printed on a payment card, separate from the embossed or printed card number. It's a security feature used specifically in situations where a PIN can't be used — a PIN isn't printed or embedded on the card, so it only works when the cardholder enters it manually at a point-of-sale terminal. The CSC fills that gap for other types of transactions.

What it's called

Every card network has its own name for this code, though they all serve the same purpose:

Term

Meaning

Used by

CAV

Card authentication value

JCB

CID

Card ID / card identification number / card identification code

Discover, American Express (4 digits, front of card)

CSC

Card security code

American Express (3 digits, back of card)

CVC

Card validation code

Mastercard

CVD

Card verification data

Discover (also used generically)

CVE

Elo verification code

Elo (Brazil)

CVN

Card validation number

China UnionPay

CVV

Card verification value

Visa

Types of code

There are a few distinct kinds of security codes, depending on how the transaction happens:

  • CVC1 / CVV1 — encoded on the magnetic stripe itself and read automatically when a card is swiped at a point-of-sale terminal, confirming the card was physically present. Its weak point is that if the stripe is cloned, this code clones with it — it doesn't stop card skimming.

  • CVC2 / CVV2 — the code most people are familiar with, requested for card-not-present transactions like phone, mail, or online orders. Some European card issuers require merchants to collect it even when the cardholder is present in person.

  • iCVV / dynamic CVV — used by contactless and chip cards, which can generate their own electronic verification codes rather than relying on a single static number.

Where to find it

The code's position and length vary by network:

  • American Express prints a 4-digit code on the front of the card, above the card number (not embossed, just printed).

  • Diners Club, Discover, JCB, Mastercard, and Visa print a 3-digit code as the last group of numbers on the signature strip on the back of the card.

  • Newer North American Mastercard and Visa cards place the code in its own separate panel next to the signature strip, rather than appended to the signature itself.