It's not quite clear what you mean here. Obviously this information is available for a given company (via the company profile endpoint or the registered office address which just gives that) and officers (for officers of a given company or Persons With Significant Control) and address information is also returned for a named company or officer by the various search endpoints.
(As always there are a few exceptions - see end of post).
Do you want to be informed if / when a company changes in some way (address change, status etc.)? There were plans to stream changes but this hasn't happened yet. For info search for "streaming api" on the forum or see e.g. thread:
If you only have a few of these you could try the "follow" service which sends you an email whenever a company makes a filing. Not so useful for automation as adding companies is a manual process.
Do you want to occasionally do a bulk update of your suppliers to check their current address? The Companies House bulk data gives you all the records for live companies and is updated every month.
It's also worth noting that the although the address object requires some work to make sense of. CH have said that what the API gives you is exactly what people enter on the form (thread here and issues discussed here) so if they don't put a correctly formatted address (or they did for places existing in 1910...) it's up to us users to make what sense we can. (Although there are presumably legal requirements about true and accurate statements etc.)
- CH don't hold address data on certain types of entities. This is normally indicated by the presence of a "
partial_data_available" member in the Company Profile object with the constant value indicating where you can find more info.
- CH have recently added some data from England/Wales (+Northern Ireland?) and Scottish charities data sets - no addresses, you just get the charity number. This is given by the "
external_registration_number" field in search results or company profile. The Charity Commission have an API for their data or you can download it all, for Scotland you need to go through their web page (or write code to scrape this information) and NI has its own search page / download).
- Overseas companies should have an address but sometimes will just have text like "SEE BRANCH REGISTRATION" or "REFER TO PARENT REGISTRY". You can always refer to their UK Establishments.
- Occasionally you see a blank address object.