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Mail drop

published · September 10, 2026 · updated · September 22, 2026

A mail drop is an address that exists to receive post for people and companies who are not there, such as a mail-forwarding branch or a formation agent.

A mail drop is an address that exists to receive post for people and companies who are not there: a mail-forwarding branch, a virtual-office suite, a company formation agent's registered-office service.

What Spaw answers

is_mail_drop is the flag, mail_drop_provider names the operator or agent where one is known, and mail_drop_source says which of three things decided it. operator_list means the address appears on a mail-forwarding operator's own published branch list. registered_agent means it is an address a registered-agent or formation service publishes, or that a public listing or filing naming the service carries. company_cluster means neither list knows it, but at least 25 companies name the address in an open company register — the published threshold, and the signal that catches a formation agent's office the list does not hold.

The risk score carries +50, and companies_registered carries the count itself so you can see the evidence rather than take the flag on trust.

What it is a fact about

An address. Not a person and not a company. Plenty of legitimate businesses use a formation agent's address, and one registered there has done nothing wrong; a cluster is a property of a building. company_cluster in particular is a heuristic with a threshold, and the number that produced it is published beside the flag for exactly that reason.

A mail drop is also not a "drop address" in the parcel-fraud sense — an ordinary address a fraudster has goods sent to for collection. Spaw holds no list of those, and the flag does not detect them. For the United Kingdom, where the registered office is a legal duty and Companies House keeps a default address for companies that fail it, see how to tell a UK virtual-office or formation address from a trading address.

Related

markdown version: /glossary/mail-drop.md

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