Companies House CLI

Terminal tool for the UK Companies House API. Look up companies, check who runs them, trace ownership, scrutinise filings, and run due diligence checks — directly from your terminal.

Get an API key

Register at developer.company-information.service.gov.uk — free, takes about 30 seconds.

Install

npm install -g companies-house-cli
ch config set-key your-key-here
ch search "Anthropic"

Commands

ch search <query>               Search companies by name
ch profile <company-number>     Company profile and status
ch officers <company-number>    Current officers (directors, secretaries)
ch ownership <company-number>   Persons with significant control (PSCs)
ch filings <company-number>     Filing history
ch charges <company-number>     Charges and mortgages
ch insolvency <company-number>  Insolvency proceedings
ch report <company-number>      Full overview in one call
ch check <company-number>       Due diligence red-flag scan
ch network <officer-name>       All companies an officer is connected to
ch search-officers <query>      Search for officers by name
ch config set-key <key>         Save API key
ch config show                  Show current key source
ch serve                        Start MCP server (stdio)
ch serve --http --port 3000     Start MCP server (HTTP)

Company numbers are 8-digit strings, zero-padded: 00445790, 14604577. Scottish companies use an SC prefix (SC123456).

Flags

| Flag | Effect | |------|--------| | --json | Raw JSON — pipe-friendly, use with jq | | --md | Markdown — good for saving to files or notes | | --key <key> | Override API key for this call only | | --all | Include resigned officers (ch officers only) | | --category <cat> | Filter filings by category (ch filings only) | | --status <status> | Filter search by company status | | --type <type> | Filter search by company type | | --sic <code> | Filter search by SIC code | | --location <loc> | Filter search by registered location | | --limit <n> | Results per page | | --id <officer-id> | Look up officer network by ID (ch network only) |

Output modes

| Mode | Flag | Best for | |------|------|----------| | Terminal | (default) | Colour-formatted, human-readable | | Markdown | --md | Saving to files, pasting into notes | | JSON | --json | Scripting, piping to jq |

API key

Checked in this order:

1. --key flag — one-off override
2. COMPANIES_HOUSE_API_KEY environment variable
3. Config file — run ch config set-key your-key to save to ~/.config/companies-house/config.json

Run ch config show to see which source is active.

MCP server

This package also ships an MCP server. Running ch serve starts it in stdio mode, which is how companies-house-mcp uses it internally. For AI assistant setup (Claude, Cursor, Zed), use the dedicated companies-house-mcp package — it handles all the wiring.

Development

git clone https://github.com/aicayzer/companies-house-mcp.git
cd companies-house-mcp
pnpm install
pnpm build
pnpm test:unit                   # no API key needed
pnpm test:integration            # requires COMPANIES_HOUSE_API_KEY

Disclaimer

Not affiliated with or endorsed by Companies House or the UK Government. Uses the publicly available Companies House API.

Licence

MIT