API key authentication
The Companies House API requires authentication credentials, in the form of an API key, to be sent with each request.
To obtain an API key, go to Your applications and register the application with
the Companies House Developer Hub as an
API Key application.
This will allocate a unique key to the application which can be sent
GET request for a public resource served by the
Companies House API.
Sending the API key
The Companies House API uses HTTP Basic Authentication to transmit an API key between the client application and the server. Basic authentication is usually made up of a username and password pair; the Companies House API takes the username as the API key and ignores the password, so can be left blank.
HTTP Basic Authentication
For an API key of my_api_key, the following curl request demonstrates the
setting of the
Authorization HTTP request header, as defined by
curl -XGET -u my_api_key: https://api.companieshouse.gov.uk/company/00000006
GET /company/00000006 HTTP/1.1 Host: api.companieshouse.gov.uk Authorization: Basic bXlfYXBpX2tleTo=