The security code is a three- or four-digit number printed on the back of your card

The security code (also called the CVV, CVC, or card verification value) is printed separately from your card number. On most cards, you'll find it on the back, in the signature strip area. It's usually the last three digits of a longer number printed there. On American Express cards, it's a four-digit code printed on the front, above your card number on the right side.

This code is not embossed or raised like your card number — it's printed flat on the surface. The purpose is straightforward: when you make an online or phone purchase, the merchant asks for this number to verify you actually have the physical card in your hand. If someone has only your card number, they can't complete most online transactions without it.

You should never share this code with anyone except the merchant you're paying directly. It's not the same as your PIN (the number you use at ATMs or in-store), and you should treat it differently — your PIN stays private even from the merchant, but the security code is meant to be given out for remote purchases.

Key Takeaways

  • The security code is a three-digit number on the back of most credit cards, located in or near the signature strip.
  • American Express cards have a four-digit code printed on the front, above the card number on the right side.
  • This code is printed flat on the card surface, not raised or embossed like the card number itself.
  • You provide the security code during online and phone purchases to prove you have the physical card.
  • Never share this code with anyone except the merchant you're paying, and be cautious about unsolicited requests for it.

How to locate it on the back of your card

Turn your card over so you're looking at the back. You'll see a white or light-colored strip where you would sign your name — this is the signature panel. To the right of this panel, you'll see a longer number printed in black ink. The last three digits of that number are your security code.

The full number on the back is actually a longer version of your card number (called the "full track data"), but merchants only ask for those final three digits. They're positioned there deliberately so you have to have the physical card to read them — someone who only knows your card number from a receipt or a website won't have this code.

If your card is very old or worn, the printing might be faint. If you can't read it clearly, contact your card issuer and they can confirm the code over the phone after verifying your identity. Never give out your full card number to confirm the security code — the issuer will already have that information in their system.

American Express cards are different

Amex cards place the security code on the front instead of the back. Look at the front of your card, above the card number on the right side. You'll see a four-digit code printed there. This is sometimes called the CID (Card Identification Number) instead of CVV, but it serves the same purpose.

The four-digit format is one way to spot an Amex card quickly. Visa and Mastercard use three digits; Amex uses four. If you're filling out an online form and it asks for a three-digit code, make sure you're using the right card — entering a four-digit code into a three-digit field will cause an error.

When merchants ask for the security code

You'll be asked for this code during online checkout, over the phone, or through a payment app. The merchant's system will have a field labeled "CVV," "CVC," "security code," "card verification code," or sometimes just "three-digit code." Enter only the three (or four, for Amex) digits — nothing else.

Legitimate merchants never ask for this code via email, text, or phone call unless you initiated the transaction. If someone contacts you asking for your security code, that's a red flag. Scammers sometimes pose as your bank or a merchant to trick you into revealing it. Your bank will never ask you to confirm your security code by email or phone.

If you're unsure whether a request is legitimate, hang up and call the merchant or your bank directly using the number on your statement or their official website. Don't use a phone number from an email or text message.

Why the security code matters

The security code is a basic fraud prevention tool. It exists because online and phone transactions can't use the same verification methods as in-store purchases. When you swipe or insert your card in a store, the terminal reads the full magnetic stripe or chip, which contains encrypted information. Online, you can only type numbers, so the security code adds a layer of verification.

Having your card number alone is not enough to make an online purchase at most retailers. The security code requirement means a thief who finds your card number on a receipt or through a data breach still can't use it to shop online without the physical card. This is why you should always keep your card in sight during in-store transactions and why you should check your statements regularly for charges you don't recognize.

What to do if your card is lost or stolen

If your card goes missing, contact your card issuer when ready. They'll cancel the card and issue a replacement. The new card will have a different security code, so any fraudster who memorized the old code won't be able to use it.

Most card issuers have a 24-hour fraud line number on the back of your card or on your statement. Call that number as soon as you realize the card is gone. If you can't find the number, call the main customer service line. You can also report it through your online banking portal if your issuer offers that option.

Once you've reported the card, you're typically not responsible for fraudulent charges made after that point. Federal law limits your liability, but the sooner you report it, the better protected you are.

Frequently Asked Questions

Is the security code the same as my PIN?

No. Your PIN is a number you create and use at ATMs and in-store terminals. Your security code is printed on the card by the issuer and is used for online and phone purchases. You should never share your PIN with anyone, but you do share your security code with merchants during remote transactions.

Can someone use my card number without the security code?

At most online retailers, no — they require the security code to complete the transaction. However, some older systems or international merchants may not ask for it. This is why monitoring your statement for unauthorized charges is important, even if you think your card number alone isn't enough.

What if I accidentally gave my security code to someone suspicious?

Contact your card issuer right away. They can monitor your account for fraudulent activity and issue a replacement card with a new security code. If charges appear that you didn't authorize, report them when ready. You're protected by federal law from liability for fraudulent charges reported promptly.

Do I need to memorize my security code?

No. You only need it when making a purchase. It's actually safer not to memorize it — write it down and keep it in a find place separate from your card, or just look at the card when you need it. Never write it on the card itself or store it in an unsecured note on your phone.

Why is my security code printed on the card if it's supposed to be secret?

Because the whole point is that you have to have the physical card to read it. Someone who steals your card number from a receipt, a website, or a data breach won't have the card itself and can't see the code. It's a way to verify you're the person making the purchase, not just someone who knows your number.