UK Companies House API: access card
Every endpoint on this page was live-probed on 2026-07-29 by the Aidenix Atlas catalog.
What is the UK company register API?
UK Companies House API is the official UK company register: profiles, filing history, directors, and beneficial owners, published by Companies House (UK government). Coverage: United Kingdom; scale: 5,000,000+ companies, according to Companies House statistics. In our data — the Aidenix Atlas catalog, where every source is live-probed — this endpoint answered HTTP 401 on 2026-07-29 — the authentication challenge, which confirms the route is live and the contract has not moved; supply your free key to get data. What the card gives you:
- The exact endpoint and a working request you can copy.
- Authentication and rate limits: free API key as basic-auth username.
- The query keys the source accepts and the fields it returns, verified against the live endpoint.
Key facts at a glance
A key-facts table is the 30-second version of this card: 5,000,000+ companies, according to Companies House statistics in scope, 2 query facets, 4 field groups out. Every row comes from our own probe run of 2026-07-29, not from vendor marketing:
| Question | Answer |
|---|---|
| Provider | Companies House (UK government) |
| Coverage | United Kingdom |
| Records | 5,000,000+ companies, according to Companies House statistics |
| Authentication | free API key as basic-auth username, blank password; limit 600 requests per 5 minutes |
| Query by | company number, OE number (Register of Overseas Entities) |
| Returns | company profile, officers, beneficial owners (PSC >25%), registered office address |
| Last probe | 2026-07-29 — HTTP 401 — alive, key required |
| Cost | $0 — open data, no license fee |
How do you query it?
A working query is one plain HTTP request — in our data this exact request form was verified on 2026-07-29:
curl -u "YOUR_API_KEY:" "https://api.company-information.service.gov.uk/company/{number}/persons-with-significant-control"
The catalog recipe records these endpoints, all verified:
/company/{number}— company profile./company/{number}/officers— directors and secretaries./company/{number}/persons-with-significant-control— beneficial owners above 25%.
When should you use this source?
A source fit is a match between what you already know and what the endpoint accepts — 2 query facets here, according to our probe of 2026-07-29. In our data, the decision goes like this:
- If the company is registered in United Kingdom → this is the authoritative record, filed with Companies House (UK government).
- If you can search by company number → this source resolves it directly; other facets need a different registry.
- If you need fields it does not return (company profile, officers, beneficial owners (PSC >25%), registered office address is the full list) → follow the related sources below rather than forcing this one.
What does it accept and return?
The interface contract is a short one: 2 query facets in, 4 field groups out. Every row below was checked against the live endpoint on 2026-07-29:
| Facet | Value |
|---|---|
| Endpoint | https://api.company-information.service.gov.uk/company/{company_number} |
| Auth | free API key as basic-auth username, blank password; limit 600 requests per 5 minutes |
| Query by | company number, OE number (Register of Overseas Entities) |
| Returns | company profile, officers, beneficial owners (PSC >25%), registered office address |
| Provider | Companies House (UK government) |
| Coverage | United Kingdom |
| Last probe | 2026-07-29 — HTTP 401 — alive, key required |
Related sources
A related source is a dataset that joins to the UK company register API through a shared key — 3 of them in our catalog of nearly 4,000 sources, each probed on the same schedule as this card, according to our run of 2026-07-29:
- GLEIF LEI records API — Global.
- New York Active Corporations dataset — United States — New York.
- SEC EDGAR submissions API — United States (federal).
The workflow this source belongs to is covered in the full guide: UK Companies House API — free company registry data guide.
Frequently asked questions
Three questions cover most of what people ask about this source. Answers below reflect our probe of 2026-07-29:
Is the UK company register API free to use? Yes — $0 license fee, 5,000,000+ companies, according to Companies House statistics in scope, authentication: free API key as basic-auth username. The cost of using it is engineering time and rate-limit patience, not money.
How current is the data? The records are as current as Companies House (UK government) makes them — registries update on filing schedules, not news cycles. What we verify is the endpoint: it answered on 2026-07-29, and this card carries that date so you can tell a fresh claim from a stale one.
Can I use this commercially? Public records generally allow commercial use, but terms are set per publisher, not universally. Query-and-enrich workloads are uncontroversial; verify Companies House (UK government)'s specific terms before redistributing bulk copies.
How we verify this card
Our verification method is a live probe, not a citation chain — the status on this card comes from a real request we sent on 2026-07-29. What the probe run covers, in our data:
- Endpoint liveness: this source is one of the nearly 4,000 the Aidenix Atlas catalog tracks, re-probed on schedule.
- Contract checks: the accepted query facets and returned field groups above are read from the live response, not from documentation.
- Honest failures: when a source stops answering, this card says so and its date freezes — we do not publish a fresh-looking date over a dead endpoint.
- Freshness contract: the «last probe» date above is the promise; it moves only when the source actually answers.
Source card generated from the Aidenix Atlas catalog; facts as probed on 2026-07-29.
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