Do you mean:
- What types of files can I supply to Companies House?
- What types of files can appear when I download a document (mime types)?
- What filing categories are available?
- What types of filing there are (essentially “what types of form can be filed” - although the old list of form types and the “enum constants” also need a mapping between…)
- Something else?
1 Types of files that can be supplied
For a very old list see here. There is current guidance on filing documents which may be more up-to-date.
2 Types of files available for download
Mime types - I believe almost all filings are available as PDF and some (many more recent account filings) are available as XML formats - XBRL and iXBRL. Per documentation you might expect “application/pdf” (PDF), “application/xml” (XBRL I think), “application/xhtml+xml” (iXBRL). And also the following - which I’ve not personally encountered: “application/json”, “application/zip” and “text/csv”.
3 Filing Categories available
The list in the documentation for the category field covers the main ones but is not complete I think.
See here for a complete list of categories and sub-categories in the data:
4 Types of filing
See the “enum constants” here. If you need a list of the old form IDs and the new identifiers search this forum, I think that’s been listed a couple of times here.