What this means
Companies House is the official company registrar for the UK. Its data is most valuable when you need a durable company identity, public filing context or a record that can be linked to other sources.
For commercial work, it should be treated as a verified starting point rather than a complete view of the business. The record tells you what has been filed. It does not guarantee that a company is active in the market you care about.
Main data sources
Core records can include company name, company number, registered office address, company status, incorporation date, filing history, officers, persons with significant control and SIC codes.
The Companies House developer site documents API access for company information. It also documents authentication and testing routes for developers who need to build against the service.
Free sources
Companies House information is publicly accessible and is often the first source used for entity lookup, company universe creation and filing checks. It can also support deduplication because company numbers are stable identifiers.
Free access does not remove the need for interpretation. Filing dates, accounts exemptions, dormant status, SIC codes and officers all need context before being used in commercial scoring.
Paid and commercial sources
Commercial providers often package Companies House records with extra fields: websites, contacts, group relationships, trading brands, categories, revenue estimates, employee estimates and risk indicators.
This packaging can save time, but it can also obscure provenance. When a vendor includes a Companies House field and a vendor-derived field side by side, keep those sources distinct in your own model.
API options
The Companies House API is the main route for programmatic lookup. Production systems should check the current official documentation for authentication, rate limits, terms and endpoint behaviour before relying on a specific integration pattern.
For reliable matching, use the company number when possible. If you must search by name, expect false positives, name changes, punctuation differences and dissolved entities.
Common use cases
Common use cases include company lookup, CRM cleaning, filing checks, officer research, PSC checks, group-structure work, market-map seeds and entity resolution.
In diligence and research, Companies House data is usually combined with company websites, press, sector directories, accounts analysis, procurement records and primary research.
Limitations
Companies House data does not provide a complete commercial profile. It may not show trading names, contacts, live websites, current headcount, technology usage, buying intent or detailed sector fit.
Small company accounts may contain limited financial detail. SIC codes can be imprecise. Registered offices may be accountants or formation agents rather than operating addresses.
Official sources
These links are starting points for source checks. Always confirm current terms, coverage, authentication and update frequency before relying on a dataset operationally.
FAQ
Is Companies House data free?
Core company information is publicly accessible. Specific access methods, bulk files and API usage should always be checked against the current Companies House documentation.
What is Companies House data best for?
It is best for legal entity identification, company numbers, filing records, officers, status checks and building a registered-company universe.
Can Companies House data be used for market mapping?
Yes, but it usually needs enrichment. SIC codes and registered records are useful starting points, but they rarely provide enough sector nuance by themselves.
Does Companies House show whether a company is trading?
It shows registered status and filings. It does not reliably describe current trading activity, brand activity, customers or live operating signals.