Companies House data developer guide
Unofficial community-driven effort to provide clear and correct guidance for working with Companies House data.
There are many footguns when using the Companies House data products. Build on other developers experience to avoid shooting yourself in the foot 🦶.
One place with documentation for many data products, compiled from various sources.
Good answers to the most commonly asked questions on the developer forum.
Companies House offers data in various ways which can be used for one-time queries, or for maintaining an up-to-date database that stays in sync with Companies House data.
In general, the REST API is good for one-time queries such as "get the registered office address for a specific company" or "which companies is this person a director of" etc.
Whereas the bulk products combined with the Streaming API make it possible to keep a database always up-to-date with the latest data. For example, you can load the basic company information data set into a database and then listen on the company events stream to update it when a companies details change.