Stop throwaway email addresses at the door
Temporary inboxes are made to be thrown away: a free trial claimed, a download grabbed, and the address dead within the hour. Prime Verifier matches every address against more than 277,000 disposable domains, refreshed daily, as part of every check.
- 277,000+ domains, refreshed daily
- Allowlist protects real providers
- Part of every check
How detection works
Two open sources, merged
The list combines two widely used open disposable-domain lists and grows as new services appear. A failed download never empties it.
Refreshed every 24 hours
New domains reach every one of our servers within an hour of each refresh.
Checked first
The domain is matched before any mail server is contacted, so a disposable address is answered almost instantly.
False positives guarded
An allowlist of major mailbox providers always wins over the blocklist.
Where to use it
- Signup and trial forms: call the API on submit and ask for a permanent address when the result is
disposable. - Existing lists: run a bulk job and drop the rows where
is_disposableis true. - Lists in your tools: turn on Remove disposable when you sync Mailchimp, Klaviyo, HubSpot or another integration.
Disposable is a definite answer, so it uses 1 credit. Catch-all, unknown and error results stay free.
Disposable email detection FAQ
How many disposable domains do you detect?
More than 277,000, merged from two widely used open lists and refreshed every 24 hours.
Could a real provider be flagged by mistake?
Major providers such as Gmail and Outlook.com sit on an allowlist that always wins over the blocklist, so a bad entry upstream cannot flag them.
Does a disposable result cost a credit?
Yes, 1 credit: it is a definite answer you can act on. It is also one of the fastest, because the domain is matched before any mail server is contacted.
Should I block disposable addresses at signup?
For free trials, gated content and anything where you need to reach the person later, usually yes: ask for a permanent address instead. The API returns disposable as its own result, so you decide.
Can I remove disposable addresses from an existing list?
Yes. Upload the list as a bulk job and filter on is_disposable, or use Remove disposable when you sync one of the 13 native integrations.
Go further
Keep throwaway addresses out of your list
Free credits on sign-up. No card. You only pay for definite answers.
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