Versioning the Companies House API

We’re planning on implementing API versioning in the near future.

The approach we’ve taken is to version our API on a per-resource basis. This allows us flexibility in developing new API features or introducing breaking changes without having to deprecate an entire version of our API, minimising the impact of non-breaking changes.

Initially, existing resources will remain as-is and will be frozen at “version 0”.

Once we’ve enabled API versioning, the latest version of the requested resource will be returned unless an earlier version is explicitly requested using the Accept header.

A preview of our API versioning documentation is available as a GitHub Gist which explains this in more detail.

We’ll provide more information on specific implementation details and resource MIME types as they become available.