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Companies House · Affix proof

Company search verification

Enter a UK company number and registered name. Affix reads the public Companies House search, confirms whether the identity matches an active registration, then anchors a signed yes or no on the Merkle audit tree.

CHPublic register
Yes / NoAffix decision
MerkleAudit leaf

Live check

Verify company identity

Number and name must both match. Letter case is ignored. Dissolved or inactive companies are recognised when the name is correct, but only active registrations return yes.

Eight-character Companies House number. Leading zeros are kept.

Must match the register exactly aside from capitalisation.

Questions

Does a dissolved company return yes?

No. A correct name on a dissolved record sets reason to dissolved and exists to true, but the Affix decision stays no until the company is active on the register.

What if the company name is wrong?

Invented suffixes or mistyped names return name_mismatch with found empty. The tool will not show another company's dissolved or active status against a non-matching name.

Where does the Merkle proof come from?

Each run calls the AffixIO yesno circuit on api.affix-io.com. The response includes proof digest, merkle root, leaf hash, and inclusion index from the live audit tree.

Is this the official Companies House service?

No. AffixIO reads the public register search. Company filings, personal codes, and ACSP identity checks stay on GOV.UK Companies House services.