# How to Stop Card Testing on Your Checkout (2026)

> Fraudsters test stolen cards with small payments on cheap plans. How to spot card testing, stop it at checkout, and keep chargebacks down.

Source: https://agentaos.ai/answers/stop-card-testing-on-checkout (canonical HTML page). Publisher: AgentaOS (Aristokrates OÜ, Estonia).

**Card testing is fraudsters checking stolen cards with small payments on your checkout. Stop it with a bot check on checkout, a limit on payment attempts per email and IP address, and no cheap plan or card-required trial for them to use.** Refund and block the test payments quickly, before the card owners dispute them.

## Seven ways to stop it

1. **Spot it** Card testing looks like a burst of small payments, most of them declined, often on your cheapest plan or a free trial that needs a card, from many cards but few emails, IP addresses or countries.
2. **Add bot protection to checkout** Put a CAPTCHA or bot check in front of the checkout or the step that creates it. Most testing is automated, so this stops the bulk of it.
3. **Limit attempts** Cap how many payment attempts one email, IP address or account can make in an hour. Real buyers rarely try more than two or three cards.
4. **Remove the cheapest target** A $1 trial or a very cheap plan is the easiest way to test a card. Raise the lowest price, or start trials without a card and ask for it at the first charge.
5. **Ask buyers to sign in first** Requiring an account with a verified email before checkout slows bots down and gives you an email to block.
6. **Refund and block fast** Refund any test payments that went through before the card owner disputes them, and block the emails and IP addresses involved.
7. **Let your payment provider screen fraud** Turn on the fraud screening your processor or merchant of record offers. A merchant of record is the seller of record, so it also handles the disputes.

## Questions

### What is card testing?

Card testing is when fraudsters use your checkout to check which stolen card numbers still work, usually with many small payments. The working cards are then used elsewhere, and you get the declines, the disputes and the fees.

### Why do card testers pick my cheap plan?

A cheap plan or a card-required free trial is the lowest-cost way to check a card. Raising the lowest price or starting trials without a card removes the easy target.

### Does card testing cause chargebacks?

Yes. When the real card owners see the payments, they dispute them. Every dispute adds a fee and raises your dispute rate, which payment providers watch closely.

### Does a merchant of record protect me from card testing?

It helps. A merchant of record is the seller of record, so it handles disputes and screens payments for fraud. You still keep the cheap targets and bot access closed on your side.