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Relay address

published · September 12, 2026

A relay address is an alias handed out by a forwarding service such as Firefox Relay or SimpleLogin that delivers to a real person's real mailbox without revealing it.

A relay address is an alias handed out by a permanent forwarding service — Firefox Relay, SimpleLogin, Addy.io, DuckDuckGo Email Protection and their kind — that delivers to a real person's real mailbox without revealing it. The person controls the alias, can turn it off, and often keeps it for years; it is routinely the only address a privacy-minded customer will give a form.

What Spaw answers

The fields are is_relay and relay_service, and the domain sorts as domain_category: "relay". A relay domain sits on the open burner list because the service hands out addresses on demand, so a verifier that only reads the list reports it as disposable. Spaw does not: disposable is forced false for a relay, the mailbox is probed like any other, and the score carries the relay weight of 5 for the withheld identity rather than the disposable 80.

What it does not mean

A relay address is not a throwaway. The question a burner list answers — will this inbox exist tomorrow — has a different answer here from the one a signup form is asking — will this person still read mail sent to it in a year. The alias can be switched off by its owner, which is a reason to keep the relationship worth keeping rather than a reason to refuse the address.

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markdown version: /glossary/relay-address.md

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