Companies
Company registers, identifiers and filings
Company APIs give official company registers and identifiers: UK companies and their officers, the global LEI register and the filings of US-listed companies. Use them to check a business partner or show a company's financial results.
Companies House API
The Companies House API gives the UK register of companies: search companies, and get their profile, registered address, officers, persons with significant control, charges and filing history, for example to check a supplier. ...
GLEIF LEI API
The GLEIF API gives the global register of Legal Entity Identifiers (LEIs): the official name, address, legal form and parent companies of more than two million companies and funds worldwide, for example to check a business ...
SEC EDGAR APIs
The SEC EDGAR APIs give the filings of companies listed in the United States: each company's filing history and financial data from its XBRL reports, such as revenue and assets per quarter, for example to chart a company's ...
Compare the company register APIs
| Service | API key | Formats | Free use |
|---|---|---|---|
| Companies House API | Needed, free | JSON | Free with a free API key, up to 600 requests per five minutes. |
| GLEIF LEI API | Not needed | JSON | Free, no key needed. |
| SEC EDGAR APIs | Not needed | JSON | Free, no key needed. |
Questions
Which free company register APIs work without an API key?
GLEIF LEI API and SEC EDGAR APIs work without a key, according to their documentation. Most keyless services ask you to keep the number of requests reasonable, and some ask for a User-Agent that names your app.
Are these company register APIs really free?
The services here can be used without paying, at least on a free plan or free tier, often with limits such as a number of requests per day or non-commercial use only. The table above quotes what each service says about its free use; check the provider's own terms before you rely on it.
How up to date is this list?
The address of every service is checked about once a week, and services that stop working or stop being free are removed. This list last changed on November 8th, 2026.