EMV chip cards, explained for merchants.

EMV chip cards carry a small computer chip that creates a unique, one-time code for every in-person transaction, so copied card data can’t simply be reused to make a counterfeit card. For merchants, accepting EMV chip cards on a chip-enabled terminal reduces counterfeit fraud at the counter and keeps you on the right side of the card brands’ liability rules.

EMV is named for Europay, Mastercard and Visa, the companies that created the original standard. Today it is managed by an industry body that includes the major card brands. This guide covers how chip payments work, what the liability shift means, how contactless payments fit in and where chip cards don’t help.

How a chip payment works

A magnetic stripe holds the same data every time it is swiped. If a criminal copies that data with a skimmer, they can write it onto a blank card and use it again. A chip works differently:

1. The customer inserts or taps the card.
2. The chip and the terminal exchange information.
3. The chip generates a one-time code, called a cryptogram, for this transaction only.
4. The code travels with the authorization request to the card issuer, which checks it.
5. If the code is valid, the issuer approves the payment. The same code won’t work again.

Because each code is good for only one transaction, data stolen from a chip payment is much harder to turn into a working counterfeit card. That is the core benefit of EMV.

The liability shift

In 2015, the major card brands shifted liability for counterfeit card fraud on in-person transactions in the U.S. In plain terms, when a counterfeit card is used, the party with the weaker technology generally bears the loss. If the customer had a chip card but the merchant swiped it on a terminal that couldn’t read chips, the merchant may be responsible for that counterfeit fraud chargeback.

Card	Terminal	Who generally bears counterfeit fraud
Chip card	Chip-enabled and used	Issuer
Chip card	Swipe only	Merchant
Magnetic stripe only	Chip-enabled	Issuer
Magnetic stripe only	Swipe only	Issuer

Some categories, such as automated fuel dispensers, were given later dates. The exact rules vary by card brand and fraud type, so check with your processor if you have unusual equipment. The practical takeaway is simple: if your terminal can read chips, have customers dip or tap, not swipe. For more on disputes, see chargebacks explained.

Chip, tap and mobile wallets

Contactless, or tap-to-pay, uses the same EMV technology. When a customer taps a card, the chip creates a one-time code just as it does when the card is inserted. Mobile wallets on phones and watches go a step further by replacing the real card number with a token, so the merchant never sees the actual number.

• Insert (dip): the chip creates a one-time code. The card stays in the reader until the payment finishes.
• Tap: same protection, faster checkout, no card handed over.
• Mobile wallet: one-time code plus a token in place of the card number.
• Swipe: static data with no one-time code. Use it only as a fallback when the chip can’t be read.

Many card brands have also made signatures optional, so the verification step varies. Some cards use a PIN, some use no verification for smaller amounts, and terminals handle this automatically. Our guide to tokenization and encryption explains tokens in more detail.

What chip cards don’t stop

EMV is very good at one job: stopping counterfeit cards at the counter. It doesn’t solve every kind of fraud. It doesn’t protect:

• Online and phone orders. No chip is read, so card-not-present fraud needs other tools, such as address and security-code checks.
• Lost or stolen cards. A real card in the wrong hands still has a working chip. PIN verification helps where it is used.
• Fallback swipes. If a chip card is swiped because the chip “didn’t work,” the protection is gone. Watch for repeated fallbacks.
• Friendly fraud. A customer disputing a real purchase isn’t stopped by any card technology.

Chip cards also don’t make you PCI compliant on their own. They reduce counterfeit risk, but your network, staff habits and questionnaire still count. See card fraud prevention for a wider view.

Getting the most from your chip terminals

Having chip terminals is the first step. Using them well is the second. A few habits make a real difference:

• Turn on contactless. Tap is fast and keeps the card in the customer’s hand.
• Train staff not to swipe chip cards. Swiping a chip card by habit gives up the liability protection.
• Track fallback. If one terminal falls back to swipe often, have it checked.
• Keep firmware current. Terminal updates fix bugs and keep card-brand certifications in order.
• Inspect for tampering. Skimmers and overlays still appear on chip terminals. Check devices regularly.
• Plan for mobile and outdoor sales. Use chip-capable mobile terminals for events, deliveries and tableside payments, rather than phone-based swipe readers.

If you are shopping for new equipment, our guide on how to choose a card terminal walks through the options.

What PayZoom does

PayZoom supplies chip and contactless terminals, including Dejavoo and Valor models, and sets them up to read chips and taps on every transaction. Browse our terminals and POS options, or keep the equipment you have. We are platform-agnostic and fit processing to your POS where we can.

We also help you stay PCI compliant with no non-compliance fees, and a real person answers when a terminal acts up. Start with a free statement analysis, or call 866.242.4325.