Companies House MCP servers compared (October 2026)

Quick comparison

The first decision is whether you need financial figures. If you only need register data, officers and PSCs, a free open-source server with your own Companies House key does the job.

"Financial figures" means balance sheet or profit and loss numbers returned as data. Servers without them can still fetch the accounts document, and a capable model can sometimes read figures from it, but that costs tokens and is error-prone on multi-year iXBRL files.

How we compiled this

We read each server's README, tool list and pricing on 17 October 2026 and checked repository metadata on GitHub. We did not run a formal benchmark of every server, so the table describes what each server says it does. GitHub search returned 49 repositories for "companies house mcp"; we list those that are maintained, documented or notable, not every fork.

Hosted servers with financial data

Registrum

Registrum's hosted server at https://registrum.co.uk/api/mcp works with no key and no sign-up, which no other server here offers. Anonymous use is capped per tool per day: for example 30 searches, 10 company lookups and 2 financials calls. Its nine tools cover company bundles, profiles, directors, ECCTA compliance, PSCs, PSC chains up to the ultimate owner, director networks and iXBRL financials (turnover, net assets, profit and employees for the current and prior year).

Paid plans: Web £9 a month (500 calls), Pro £49 a month (4,000 calls, PSC chain and compliance endpoints), Enterprise custom. The client is MIT-licensed on GitHub as RegistrumUK/uk-companies-house-mcp.

Best for: trying a Companies House MCP server in one minute, and ownership chains.

CompanyStack

CompanyStack includes MCP access on all its API tiers, at https://api.companystack.co.uk/mcp, with tool calls counted as API requests. Its data covers accounts since 2008, which it describes as 24.8 million years of accounts for 3.6 million active companies. The free API tier allows 1,000 requests a day; Starter is £29 a month for 10,000 a day. It needs an API key, and we could not confirm the tool list from a public page.

Best for: high-volume agents that need financials on a small budget.

UK Company Data (ours)

Our server at https://data.globalmindsetmarketing.co.uk/mcp exposes 11 tools: search_by_name, lookup_company, compare_companies, search_companies, find_triggers, market_stats, recent_changes, watch_add, watch_list, watch_remove and get_alerts. It covers the full register and balance sheet figures from about 37 million iXBRL filings from 2008 to 2026, plus a watchlist that raises alerts for status changes, overdue accounts, new charges and falling net assets or cash.

It needs a free key (50 requests a month); Pro is £39 a month for 5,000 requests. It does not cover officers or PSCs yet. Setup for Claude, ChatGPT, Cursor and Claude Code is on our MCP server guide.

Best for: multi-year balance sheets, screening by financial signals and monitoring a portfolio of companies.

DataLedger

DataLedger publishes dl-mcp, a small server you run locally (stdio or HTTP) with two tools: company search with financial filters and company details. It needs a DataLedger API key; the API starts with 25 free credits, then £10 a month for 300 credits.

Best for: filtering companies by financials inside an agent, if you already use DataLedger.

Open-source servers that wrap the official API

These servers call the Companies House API with your own free key, so they are as current as Companies House itself and cost nothing beyond your hosting. They share its limit of 600 requests per five minutes per key, and none returns parsed financial figures.

stefanoamorelli/companies-house-mcp

The most complete wrapper, written in TypeScript under AGPL-3.0, with over 45 tools covering profiles, search (including dissolved companies and disqualified officers), officers, filing history, PSCs and PSC statements, charges, insolvency, exemptions and UK establishments. It was last updated in June 2026. The AGPL licence matters if you plan to offer it as part of a hosted service.

Best for: full coverage of the official API in one server.

aicayzer/companies-house-mcp

A TypeScript server under MIT, actively maintained (last push October 2026), with about 18 tools including officer networks, ownership, filings and filing document download. It runs locally with no proxy in between, and doubles as a command-line tool.

Best for: a maintained, permissively licensed local server.

paulieb89/uk-due-diligence-mcp

A Python server under MIT that combines Companies House (profiles, officers, PSC chains, charges, disqualifications) with other UK sources: Charity Commission, Gazette insolvency notices, HM Land Registry price paid data and sanctions lists. It needs a Companies House key and also has a hosted deployment.

Best for: due diligence across several UK public registers at once.

Smaller projects

• elankeeran/Companies-House-MCP-Server: Python, MIT, 22 tools aimed at KYB, including document download. Last updated January 2026.
• St3v3a/companies-house-mcp: JavaScript, MIT, about 10 tools, listed on Smithery. Last updated January 2026.
• DarkhorseOne/companies-house-mcp: TypeScript, MIT, 4 basic tools; not updated since July 2025.

Which to choose

1. You only need register data and want it free: aicayzer or stefanoamorelli with your own Companies House key.
2. You want to try MCP with no setup: Registrum.
3. You need financial figures: Registrum for the latest two years, CompanyStack or UK Company Data for history since 2008.
4. You need monitoring: UK Company Data's watchlist and alerts, or Registrum's company watch (1 company free, more on paid plans).
5. You need ownership chains: Registrum Pro.

Whichever you choose, check the figures against the filing for anything that matters. On 1 October 2026, 26.0% of active companies had not filed any accounts yet (accounts types data), so every server will return no figures for about a quarter of companies.

FAQ

Is there an official Companies House MCP server?

No. As of October 2026 Companies House offers a REST API, a streaming API and bulk data, but no MCP server. Every server listed here is built by a third party on top of that open data. Some describe themselves as unofficial in their README, which is accurate for all of them.

Which Companies House MCP server works without an API key?

Registrum's hosted server works with no key and no sign-up, within small daily caps per tool. All open-source servers need your own free Companies House API key, and CompanyStack, DataLedger and UK Company Data need a key from their own service. Our free key takes about a minute to get on the developer docs page.

Can an MCP server give Claude a company's turnover?

Only when the company filed it and the server parses accounts. Registrum, CompanyStack, DataLedger and UK Company Data return figures from iXBRL accounts. Most small companies do not file a profit and loss account, so turnover is often missing even then. Servers that wrap the official API return the accounts document, not the figure.

Are open-source Companies House MCP servers safe to use?

They run with your own API key, so review the code before installing, pin a version and keep the key out of shared configuration. The Companies House API is read-only, which limits the damage a faulty server can do, but a server could still leak your key or exhaust your rate limit. Prefer maintained projects with recent commits.

Sources: Companies House register and accounts data (Open Government Licence v3.0), legislation.gov.uk and GOV.UK guidance where linked. This page is general information, not legal, tax or credit advice. Spotted an error? Email info@globalmindsetmarketing.co.uk.