A new supplier sends an invoice with a company registration number on it.
Is the company real, still trading, and up to date on its filings? answers from Companies House by company number — and from Brønnøysundregistrene / Enhetsregisteret (brreg) by organisasjonsnummer (orgnr, org.nr), with the same tool and the same JSON.
The prompt Invoice from Tesco PLC, company number
00445790.
Is it active, and is it up to date at Companies House?
The call Read the s literally.
Companies House publishes no VAT status and no employee count, for any company — means "this register does not say", never "no".
Norway publishes both: One shape, two registers, honest about which publishes what.
The half that's actually useful Companies House publishes each company's own filing due dates, so quotes them rather than guessing.
Deloitte's LLP, on 4 September 2026: is not a stale response.
Companies House leaves an overdue date in the past instead of rolling it forward, so the negative number is the answer: that confirmation statement is three weeks late.
UK deadlines never move off a weekend or bank holiday either — a Sunday deadline is a Sunday deadline in law. says whether a date is quoted or computed; quote it.
Two things that will trip your agent The country code is , not .
Every error names its own fix in .
A UK company number has no check digit.
So is a normaliser first: Short numbers are zero-padded, prefixes upper-cased ( → ).
But means the shape is right, nothing more: a mistyped UK number is well-formed and comes back .
Norway's MOD11 catches a transposed digit; the UK has nothing to catch it with.
And sole traders and ordinary partnerships are not on the register at all, so a missing UK business is often a real one.
Companies House data: Crown copyright, free to re-use.
Norwegian data: Enhetsregisteret, NLOD 2.0.
Same JSON over MCP and REST.
Repo: https://github.com/foretak/registry-mcp