Payment Fraud Prevention for Ecommerce: 10 Checkout Checks Merchants Should Run in 2026

Introduction

"Fraud remains a universal challenge, with 98% of merchants experiencing one or more types of fraud in the past 12 months," according to the Merchant Risk Council 2025 Global eCommerce Payments and Fraud Report, which surveyed 1,082 merchant payment and fraud professionals.

If nearly every merchant sees fraud, the real question is not whether it will reach your store. It is whether your checkout catches it before you ship the goods.

This guide is a practical checklist. It covers ten checks you can run on every card payment, what each one tells you, and where each one falls short. No single check stops payment fraud on its own. Layered together, they give you a clear picture of each order without punishing good customers.

What Is Payment Fraud Prevention at Checkout?

Payment fraud prevention is the set of checks a merchant runs before accepting a payment and releasing an order. The goal is to spot stolen cards, card testing, and account misuse early, while keeping approval rates healthy.

Payment fraud detection happens in two places. Your payment processor and the card issuer run their own checks. You add context they cannot see, such as order history, delivery details, and how the shopper reached your site. The ten checks below sit on your side of that line.

1. Run an Address Verification System (AVS) Check

An AVS check compares the billing address the shopper enters with the address the card issuer has on file. In most cases, it compares the numeric parts, such as the house number and postal code.

Your processor returns a result code: full match, partial match, no match, or unavailable. A full match is a good sign. A partial match is common and often innocent, for example after a recent move. A no match on a high-value order deserves a second look.

Keep in mind that AVS support varies by country and issuer. Treat "unavailable" as missing data, not as a fraud signal.

2. Require a CVV Check on Every Card-Not-Present Payment

The CVV check confirms the three or four digit security code printed on the card. A correct code suggests the shopper has the physical card or its full details, not just a leaked card number.

Make the field mandatory and decline or review mismatches. Never store the code after authorization. PCI DSS rules prohibit keeping it, and stored codes are exactly what attackers look for.

3. Use 3D Secure Where Risk Justifies It

3D Secure adds an authentication step run by the card issuer, such as an app approval or a one-time code. Modern versions use a risk-based flow, so many low-risk shoppers pass without any extra step.

3D Secure is run through your payment provider, not your fraud tool. In regions with strong customer authentication rules, such as the European Economic Area, it is often required. Elsewhere, you can trigger it selectively for riskier orders. Successful authentication can also shift chargeback liability for certain fraud disputes to the issuer, depending on card network rules.

4. Check the Card's BIN Against the Order

The first six to eight digits of a card are its Bank Identification Number (BIN). A Greip BIN Lookup returns the issuer, card scheme, card type, and issuing country.

Compare that information with the rest of the order. A prepaid card from one country, a billing address in another, and an express delivery request to a third is a pattern worth reviewing. BIN data does not prove card ownership or available funds. It adds context that makes other mismatches easier to judge.

5. Compare IP Location With Billing and Shipping Details

The shopper's IP address gives an approximate location. With Greip IP Location Intelligence, you can see the country, city, time zone, and network behind each checkout.

A gap between IP country and billing country is not proof of fraud. Travelers and expats create these gaps every day. The signal gets stronger when it lines up with other warnings, such as a new account, a high-value basket, and a mismatched card country.

6. Flag VPNs, Proxies, and Hosting Networks

Fraudsters often hide their real location behind anonymizing services. Greip VPN and Proxy Detection shows when a visitor connects through a VPN, proxy, Tor, or hosting network.

Do not block every VPN user. Many people use them for privacy or work. Instead, raise the risk score, ask for extra authentication, or send the order to review when a VPN appears alongside other red flags.

7. Validate Email and Phone Details

Throwaway contact details are a common feature of fraudulent orders. Greip Data Scoring and Validation helps you spot disposable email domains, invalid formats, and risky phone numbers at checkout.

These checks assess risk. They do not confirm that a specific inbox exists or that the shopper owns the phone. Use them as one input among several.

8. Set Velocity Limits to Stop Card Testing

Card testing is when fraudsters push many small payments through your checkout to find out which stolen cards still work. Velocity limits cap how many attempts can come from one card, account, device, or IP in a short window.

Watch failed payments as closely as approvals. A burst of declines, followed by one success, is a classic testing pattern. Add rate limits or a challenge step when attempts spike.

9. Score the Whole Transaction, Not Single Signals

Each check above answers one narrow question. A transaction risk score combines them, so you can see whether several signals point the same way. Greip Payment Fraud Analysis helps you assess transaction risk using details such as the card, IP, customer, and order context.

Use the score to decide between three outcomes: approve, review, or decline. Tune the thresholds to your own products and margins rather than copying someone else's rules.

10. Route Flagged Orders to a Clear Review Process

Checks only help if someone acts on them. Give your team a short playbook: what to verify, how long an order can wait, and who makes the final call.

Contact the customer through a channel you already trust, not a new one supplied during the risky checkout. Record every decision and its reason. That record becomes training data for your next round of rule changes.

How to Measure Whether Your Checks Work

Track fraud chargebacks, false declines, manual review rate, and approval rate together. Cutting fraud while rejecting good customers is not a win.

Review results monthly. If a rule flags many legitimate orders but catches little confirmed fraud, loosen it. If one product line attracts repeated disputes, tighten checks there only.

Frequently Asked Questions

What is an AVS check?

An AVS check compares the billing address a shopper enters with the address the card issuer has on file, usually the house number and postal code. The processor returns a match, partial match, no match, or unavailable result that you can use in your fraud decision.

How does BIN lookup help prevent payment fraud?

A BIN lookup reveals the card's issuer, scheme, type, and issuing country from its first digits. Comparing that data with billing, shipping, and IP details helps merchants spot mismatches, such as a foreign prepaid card on a high-risk order, before approving it.

How does IP data flag risky orders?

IP data shows a shopper's approximate location and whether they use a VPN, proxy, or hosting network. When IP location conflicts with billing or shipping details, or hides behind an anonymizer, it adds risk context that supports a review decision.

Is 3D Secure enough to prevent payment fraud?

No. 3D Secure adds issuer authentication and may shift liability for some fraud disputes, but it does not stop refund abuse, account takeover, or every card testing attack. Combine it with AVS, CVV, BIN, IP, and velocity checks.

Conclusion

Payment fraud prevention works best as a layered checklist, not a single tool. Run AVS and CVV checks, use 3D Secure where risk justifies it, add BIN, IP, and contact data context, cap velocity, and score the full transaction.

Start with the checks your processor already supports, then add risk data where your losses are highest. Review your results every month, and keep the experience smooth for the customers who are exactly who they say they are.