Disposable email

What they are

A disposable address comes from a service built for throwaway use: Mailinator, Guerrilla Mail, 10 Minute Mail, and many thousands of others. The inbox is public or short-lived, and the domain rotates constantly to evade blocklists.

Why they appear in your data

Nobody mails a real contact at one on purpose. They arrive through sign-up forms, free-trial lead magnets, and gated downloads, where the visitor wanted the content and not the follow-up. A scraped or purchased list can be full of them.

Why they are a problem

• The address works for a few minutes or days, then stops. A later send bounces or goes nowhere.
• A real person is not behind it, so it can never produce a reply.
• Mailing disposable domains is a signal of poor list hygiene.

How detection works

There is no single test. Detection is mostly a maintained list of known disposable domains, extended by heuristics: a newly registered domain, an MX record pointing at a known disposable provider, a wildcard mailbox behaviour. Because the list never stops growing, every list is incomplete. Treat a "not disposable" result as likely, not certain.

A disposable address usually verifies as deliverable, because the mailbox genuinely exists. That is why this is a separate flag and not part of the verification result. Remove them from outbound lists; and if they come from your own sign-up form, decide whether to block them there. See email verification and role addresses.