Will asking customers to verify cost me sales?

Only if you ask everyone. Verification applied after payment, to the small share of orders that score high, touches a few percent of buyers and does not affect checkout conversion at all.

Is it legal to ask for a government-issued document?

In most markets yes, provided you have a legitimate anti-fraud basis, tell the customer why, store the document securely with restricted access, and delete it once the check is complete. Keep the request proportionate to the order value.

What if the customer never responds to the verification email?

Set a deadline — typically 48 to 72 hours — and cancel with a refund if it passes. Genuine customers respond quickly; a silent inbox on a high-risk order is itself the answer.

Verifying high-risk customers without killing conversion

Verification only hurts conversion when you apply it to everyone. Target it properly and the friction lands on fraudsters, not customers.

Verify after payment, not during checkout

Every extra field at checkout costs conversion across all of your traffic. Verification placed after the order is paid costs conversion on none of it, because the buyer has already committed.

The trade-off is timing: you must hold fulfilment while you wait. That is fine as long as the hold applies to a small, well-chosen minority of orders.

Use tiers, not a single rule

Low risk: no contact at all. This should be the overwhelming majority of orders.
Medium risk: a verification email to the exact address used at checkout. One click, no account needed.
High risk: a government-issued document matching the cardholder's name, reviewed before dispatch.
Extreme risk or repeat abuse: cancel and refund, and block the identifiers you are confident about.

Why email verification works so well

A stolen card comes with card details, not inbox access. Asking the buyer to confirm from the checkout address filters out a large share of true fraud at almost zero cost to real customers.

It also creates a durable artefact: a timestamped confirmation from the account holder that is genuinely useful if a dispute is filed later.

Word the request so it does not feel like an accusation

Lead with the reason: a routine security check on this order before dispatch.
State exactly what you need and how long it takes.
Give a clear deadline and say what happens if it passes.
Send it from your own store name so it does not look like phishing.
Confirm in writing the moment the check clears, and ship immediately.

Measure the friction you add

Track three numbers: the share of orders asked to verify, the completion rate, and the dispute rate of orders you let through unverified.

If more than a few percent of orders are being challenged, your thresholds are too tight and you are taxing good customers. If disputes still appear below your verification threshold, it is too loose. Adjust monthly and the system tunes itself.

Frequently asked questions

Will asking customers to verify cost me sales?: Only if you ask everyone. Verification applied after payment, to the small share of orders that score high, touches a few percent of buyers and does not affect checkout conversion at all.
Is it legal to ask for a government-issued document?: In most markets yes, provided you have a legitimate anti-fraud basis, tell the customer why, store the document securely with restricted access, and delete it once the check is complete. Keep the request proportionate to the order value.
What if the customer never responds to the verification email?: Set a deadline — typically 48 to 72 hours — and cancel with a refund if it passes. Genuine customers respond quickly; a silent inbox on a high-risk order is itself the answer.