What verification does
An email verifier checks whether an address can receive mail, without sending an email. Typical checks:
- syntax — is it a valid email format?
- domain — does the domain exist and accept mail (MX records)?
- mailbox — does the server say this specific mailbox exists?
- risk flags — disposable, role-based, known spam traps.
Why bounces matter
Inbox providers watch your bounce rate. Sending to many invalid addresses signals a poor list — a classic spammer pattern — and hurts where your future emails land.
Catch-all domains
Some domains accept mail for any address, so a verifier can't confirm whether a specific mailbox exists. These are reported as "catch-all" or "unknown". They're not necessarily bad — many small businesses use catch-all setups — but treat them as higher risk and send to them carefully. See catch-all emails explained.
Emails found on websites
Emails Prospect Cheap finds on a business's own website are usually real, published addresses — a good starting point. But websites go out of date: a staff member leaves, a domain changes. The email status column flags addresses that look problematic.
When to verify
- before large sends (hundreds or thousands)
- when the list is more than a few weeks old
- when using new sending domains still warming up
- when your bounce rate starts rising
What to do with results
- valid: send
- invalid: remove
- catch-all / unknown: send in small batches, or reach by phone or social instead
- role-based (info@): keep for small businesses where the owner reads them
Related: cleaning a lead list · deliverability basics