Get started

Register a Companies House user account

You must register a user account with Companies House to explore and perform tests with the Companies House API.

To get started quickly, each Companies House API reference page contains an embedded explorer to try out the service without having to write any client code.

About the Companies House API

Companies House digitally records almost all the information it receives and makes this available to the public through its website and through the Companies House RESTful API.

Being RESTful, each record of information is assigned a globally unique URI, and the operations available on each resource are directly mapped to HTTP verbs. Data can be easily consumed by issuing simple GET requests on the required resource URI.

Read the Companies House REST API overview for more information about our API approach, REST web services and the JSON data format.

API authentication

Access to API services requires authentication. The Companies House API requires API authentication credentials to be sent with each request, which is sent as an API key, stream key or OAuth access token.

Learn how to create an application as well as API keys, stream keys and OAuth web clients.

Developer guidelines

Read the developer guidelines for information about security, API rate limits and enumerated types as you’re developing your application.