Blog
What Retailers Need to Know About Credit Card Testing Fraud and How to Fight It
June 6, 2025 / 6 minute read / By Michele Salerno

Blog
It’s called credit card testing, and it’s quickly becoming one of the most financially damaging types of eCommerce fraud today.
For small to medium retailers, understanding and preventing this type of fraud isn’t just important. It’s essential for protecting your bottom line and maintaining customer trust.
We break down some simple steps retailers can use to fight credit card testing and fraud:
Understanding how these attacks work and ensuring your checkout is adequately protected can significantly reduce your exposure and avoid being hit with thousands in unwanted fees. More importantly, it protects your business’s reputation and maintains the trust your customers place in you.
Credit card testing happens when criminals purchase stolen card numbers on the dark web and “test” them online to see which are still active. They typically use bots to run hundreds, or even thousands, of small-dollar authorization attempts through a retailer’s online checkout. Cards that process successfully are flagged as valid and then resold on the black market at a premium.
The problem? The system doesn’t immediately reject these authorization attempts. Even if most are declined, each one still passes through your payment processor, resulting in processing and authorization fees for your business.
In some cases, retailers have lost a few hundred dollars. In others, we’ve seen damages exceed $150,000 in processing fees alone, with no legitimate purchases involved. For smaller retailers operating on tight margins, even a few thousand dollars in unexpected fees can significantly impact operations and cash flow.
Small to medium retailers are particularly vulnerable to credit card testing fraud for several reasons:
In the fight against fraud, prevention is always more cost-effective than recovery. Invest in proper protection today, and save yourself from potentially devastating losses tomorrow.
These attacks often bypass your eCommerce platform entirely. They occur directly through the payment processor’s iframe, the embedded payment form hosted by your processor. Your platform may have no visibility or control because the fraud happens inside the processor’s environment.
That’s why your choice of payment processor matters just as much as your eCommerce provider. Look for a processor with built-in fraud prevention tools and ensure they’re activated and properly configured.
Recommended protections include:
Not all credit card processors offer these protection tools by default. Confirm with your provider what’s available and what’s turned on. If you can, learn about their other software offerings and evaluate what can fit your budget as well as what you think your business needs most.
Learn More: 5 Facts About Online eCommerce for Retailers
Before switching to a new payment processor, ask them how they handle credit card testing fraud and similar attacks. Unfortunately, these incidents happen more often than retailers would like, so most reputable processors are well aware of the problem.
Many processing partners have been flexible and collaborative, often crediting processing fees to the merchant when such fraud occurs. Some even take the next step by assisting merchants with the Visa fee credit request process.
However, this level of support can vary by processing vendor, so it’s essential to clarify their policies upfront
Key Questions to Ask Potential Processors:
An effective processor will have clear procedures to:
Understanding how your processor typically addresses these unfortunate scenarios and partners with merchants during them can save you headaches and help you choose the best fit for your business.
What Retailers Can Do:
The sophistication of these attacks is increasing rapidly. Criminals are using artificial intelligence and machine learning to make their attacks more difficult to detect. They’re also targeting smaller retailers who may have less robust security measures in place.
Credit card testing fraud is especially frustrating because these transactions aren’t “fraudulent” in the traditional sense; they’re real authorizations. But the intent is criminal, and the costs to you are real.
Don’t wait until you become a victim of credit card testing fraud. Contact your eCommerce provider if you’re unsure whether your current checkout setup includes these protections. They can help assess your risk and work with your payment processor to strengthen your defenses.
Suppose you’re ready to partner with a provider that takes fraud prevention seriously. In that case, Celerant’s comprehensive retail management platform includes built-in fraud protection through partnerships with industry leaders like Signifyd and ClearSale.
Our team understands the unique challenges facing small to medium retailers. It can help you implement a fraud prevention strategy that protects your business without hindering legitimate sales.