Is there anything similar to Companies House (UK) but in the US?

Answer 1

I'm in the US, so I'm not entirely sure about everything that Companies House does.

Information on public companies is available from the SEC - quarterly and annual reports and other required filings. The information is filed using a system called EDGAR, linked below.

States handle the incorporation and dissolution of corporations and similar entities. That information is handled by each state's Secretary of State.