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What's My Credit Card CVV?

John Egan

Aside from the card number itself, the CVV is one of the most important numbers on your credit or debit card. This three- or four-digit code is designed to prevent fraud.

"The CVV was first devised as an anti-fraud mechanism," says Monica Eaton-Cardone, co-founder and chief operating officer of risk mitigation and chargeback management firm Chargebacks911. "The idea was to target card-not-present fraud by asking for a simple code that should be easy for legitimate cardholders to provide, but is unknown to a fraudster."

Card-not-present fraud refers to fraud committed when a purchaser does not physically present a card for online, telephone or mail-order transactions and spends with a card he or she is not authorized to use. Typically, card details are obtained through hacking, skimming or other methods and then used to facilitate the transactions.

Today, most credit and debit cards issued have a CVV. But what does that mean for cardholders?

What Does CVV Stand For?

CVV stands for card verification value but can serve as a catch-all term for the security code on credit cards. Each credit card company has its own name for it, such as CVV2, for card verification value code; CSC, for card security code; CVC or CVC2, for card verification code; or CID, for card identification number, according to card issuer Discover.

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The differences don't stop there, though. Visa, Mastercard and Discover use three-digit security codes, while the American Express security code is four digits.

Whatever its length or name, the CVV is not part of your credit card number, debit card number, PIN or expiration date. These numbers are all separate from each other.

Where Can I Find the CVV?

The location of the CVV code may differ from card to card. The standard location for security codes on Visa, Mastercard or Discover is the back, at the far-right side of the box where you are supposed to sign the card. The four-digit security code for an American Express card is usually on the front, above the credit card number. Some cards may have the security code in another location, such as on the back, below the credit card number.

Contact the card issuer if you're having trouble locating the security code or if the code is worn down to the point that it's hard to read.

How Does My CVV Work?

Card security codes are a form of two-factor authentication. Two-factor authentication relies on two pieces of information -- such as a credit card number and a CVV -- to confirm you are the cardholder. The CVV verifies that the card is in your possession and, as a result, helps prevent fraud, Eaton-Cardone says.

"If a buyer can correctly enter the card's CVV during checkout, it's likely the person at least has the card in her physical possession. That makes it harder for criminals to use stolen cardholder information to make fraudulent purchases," Eaton-Cardone says.

Entering the wrong code should result in a transaction being declined, says Nicolas Beique, founder and CEO of payment processing platform Helcim.

Merchants -- even online businesses you buy from regularly, such as Amazon -- are prohibited from storing card security codes in their databases. That way, if a database is compromised, hackers can't access the security codes needed to use the stolen card numbers, Beique says. But they can tap other methods to get your CVV code, including stealing your sensitive information online through phishing and keylogger scams.

Always closely guard your card's security code. If a thief has your credit card number, expiration date and security code, that is all the information he or she needs to make an online purchase.

How Much Security Does a CVV Offer?

A CVV code is an added layer of protection that makes fraud difficult but not impossible.

"There is a reduced chance that your account will be used to make unauthorized purchases when someone obtains your credit card number without the CVV code," says Bruce McClary, vice president of communications for the National Foundation for Credit Counseling. "You may still be vulnerable in situations where the card is used without your permission on a website that does not require the CVV code to be entered."

Cybercrimes present additional risks. Cyberthieves can employ software known as malware to steal security codes from retailers.

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CVVs also are susceptible to phishing attacks, when scammers use fraudulent emails or copycat websites to trick cardholders into sharing sensitive information, including security codes. A common scam is spoofed texts or phone calls that look like they come from your credit card company and ask for your CVV to verify a recent purchase. If you receive a similar communication, ignore it and call your credit card issuer.

In light of those examples, security codes are only one part of a broader strategy for detecting criminal fraud, Eaton-Cardone says. For example, PNC Bank announced in November 2018 that it is testing a technology called Motion Code, which automatically refreshes the security code on a miniscreen on the back of the card.

With this new technology, Eaton-Cardone says, "Even if a fraudster manages to steal the code, it will be invalid by the time it's used. This means CVV will continue being a valuable anti-fraud tool for the foreseeable future."

How Can I Protect My CVV?

To avoid becoming a victim of credit card fraud, here are four tips for safeguarding your credit card CVV.

-- Don't post photos of your credit card, including the CVV, on Facebook, Twitter or other social media platforms.

-- Install anti-virus software on your computer to shield credit card information, including the CVV, from scammers when you're shopping online. Among Eaton-Cardone's recommendations are Webroot SecureAnywhere AntiVirus, Bitdefender Antivirus Plus, Kaspersky Anti-Virus, AVG AntiVirus, Avast Free Antivirus and Norton AntiVirus Basic.

-- Ignore unsolicited requests for sensitive credit card data, including the CVV. Do not respond to or click on links in emails from unfamiliar sources.

-- Look for signs of security. Shop on secure websites equipped with secure sockets layer technology. SSL validates the identity of a website and encrypts transmitted data. An SSL site will have a padlock to the left of the URL, an https URL prefix rather than an http prefix and an SSL seal usually in the footer, near the site's copyright information. Some sites have extended validation SSL certificates -- an SSL certificate requiring encryption and data integrity -- that feature green text or a green background in the address bar.

[Read: Best Low-Interest Credit Cards.]

Do I Always Need to Use My Card's CVV?

The short answer is no. Merchants can choose whether to require the CVV code. But most online merchants do, and if you want to make a purchase with them, you'll need to provide your CVV code, usually with your credit card number and its expiration date.

In situations where a CVV is required, you need to have your card with you or have the code memorized to make a purchase, Beique says. If you're using a card in person, the CVV typically isn't required. Do not voluntarily share your CVV for an in-person transaction, which could enable a scammer to steal your data to complete unauthorized transactions.

Today, most consumers expect to be asked for a CVV when making online or telephone purchases with a credit or debit card and recognize that this is a practice typical of security-conscious merchants. However, a CVV is sensitive information, and some consumers are uncomfortable giving out the code.

In general, providing a card security code when you're shopping online is safe, as long as you're making purchases from trusted websites. Typically, it's also OK to give a CVV over the phone. Just make sure no one is eavesdropping and can hear the numbers.

One way some credit card issuers are trying to bypass the entire CVV issue is by supplying virtual credit cards with randomly generated account numbers for online purchases. Users of Bank of America's ShopSafe service can create a temporary credit card number tied directly to their real credit card number. The 16-digit account number, including a security code and an expiration date, helps safeguard your online privacy, according to Bank of America.

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