email.disposable_domain
The domain is a known disposable/throwaway email provider.
What it looks at#
An O(1) lookup of the address’s domain against an embedded list of roughly 60,900 known
disposable and throwaway email providers, built from two open, permissively-licensed
sources (disposable-email-domains/disposable-email-domains and FGRibreau/mailchecker)
and versioned through StormDoor’s reference-data pipeline — not fetched live per request.
This is a list, and lists have edges: a brand-new disposable-mail service that hasn’t been added yet will not be caught. That’s a known, stated limitation — not a claim that this check catches every disposable address that will ever exist.
Why it matters#
Disposable addresses are built to be used once and abandoned. In a signup flow they’re a strong signal that whoever’s on the other end doesn’t intend to be reachable later — common in abuse, fraud, review manipulation, and free-tier farming.
What to do#
High severity blocks by default. Some products deliberately allow disposable addresses on purpose — for privacy-conscious signups where email is never actually used to reach the person — but that’s an explicit product choice to make on top of this finding, not something to assume.