Companies House: what the free company data shows and what it does not

The United Kingdom is one of the few countries where the whole company register can be downloaded free of charge. That makes Companies House the natural backbone of any UK business list, but it is often misunderstood: the register tells you that a company exists and where it is registered, not how to reach it.

What the free snapshot contains

The Free Company Data Product is described by Companies House as a “downloadable data snapshot containing basic company data of live companies on the register”, provided free of charge and without support. It is updated within five working days of the end of each month and comes as one large ZIP file or in several parts. No registration is needed.

Each row is one live company with these groups of fields (field description (PDF)):

• company name and company number;
• registered office address (care of, PO box, address lines, post town, county, country, postcode);
• company category (type) and company status, country of origin;
• incorporation date and, where relevant, dissolution date;
• accounts and confirmation statement dates, accounts category;
• numbers of mortgages and charges;
• up to four SIC codes with their descriptions;
• up to ten previous names with the date of change.

What it does not contain: phone numbers, email addresses, websites, employee numbers or turnover.

What the snapshot shows: some figures

We read the whole snapshot of 1 November 2026. It lists 5,711,779 live companies:

• 5,179,256 with the status “Active”, 417,325 with a proposal to strike off and 107,871 in liquidation;
• 5,283,363 private limited companies, 49,867 LLPs and 4,470 public limited companies;
• 231,826 companies gave no SIC code and 103,488 gave the code for dormant companies (99999).

More tables are on our page The Companies House register in figures.

Who is missing

The register covers incorporated bodies: private and public limited companies, LLPs, limited partnerships, community interest companies, charitable incorporated organisations, registered societies and some others. Sole traders and ordinary partnerships do not register at Companies House. For a plumber trading under his own name or a two-partner accountancy firm, the register has nothing.

The registered office is also not always the place where a business trades. It can be the address of an accountant or a formation agent; the field “care of” in the snapshot often shows this. For direct mail and territory planning, a trading address from another source is often better.

The company number as a key

Every company on the register has a company number of exactly eight characters: either eight digits (for example 01234567) or two letters followed by six digits. The letters show the type or part of the UK, for example SC for companies registered in Scotland, NI for Northern Ireland and OC for LLPs in England and Wales. There is no check digit; a number is valid if it exists on the register.

Many company websites show the number in the footer, often as “Company No.”, “Registered in England and Wales No.” or “Company Registration Number”. In our analysis of UK websites, a part of the numbers was given without the leading zero (“Company No. 6168725” instead of 06168725). When matching, pad numbers to eight characters before comparing them with the register.

The UK VAT number is a different identifier: GB followed by nine digits, with a check digit calculation. Only businesses registered for VAT have one, and it is not in the Companies House data.

People with significant control

Companies House also publishes a daily PSC snapshot as JSON Lines files. It lists the people and legal entities with significant control over each company, with name, nationality, country of residence, month and year of birth and the nature of control. It contains no contact details either, and it is personal data: anyone who uses it for marketing needs a lawful basis under the UK GDPR.

The API

For live look-ups there is the Companies House API. Unlike the snapshot, it requires registering a user account and sending an API key with every request; the rate limit is 600 requests within five minutes. For bulk analysis the monthly snapshot is usually the better choice.

Can I reuse the data?

The download page states no licence. On the Companies House forum, Companies House wrote on 4 November 2021 that it “imposes no rules or requirements on how the information on the public register is used”. Data protection law still applies wherever the data identify individuals, for example in previous names, care-of addresses or the PSC data.

How to use Companies House in a B2B list

1. As a key: match your customer and prospect records by company number to avoid duplicates.
2. As a status check: remove companies in liquidation or with a proposal to strike off before a campaign.
3. As a legal-form check: a company number shows a corporate subscriber under PECR; see PECR rules for B2B email and calls.
4. Not as a contact source: phone numbers, emails and websites have to come from elsewhere.

Our exports combine map data and company websites with the company number and status from Companies House where a match is confirmed; the matching is still in progress (database status).

Frequently asked questions

Does Companies House publish phone numbers or email addresses?

No. The free snapshot contains the registered office address, company type, status, dates and SIC codes, but no phone numbers, email addresses or websites. Contact details have to come from other sources, such as the company’s own website.

Are sole traders on the Companies House register?

No. The register covers incorporated bodies such as limited companies, LLPs, limited partnerships and charitable incorporated organisations. Sole traders and ordinary partnerships are not registered there, so a list built only from Companies House misses them.

Do I need an account to download the data?

Not for the snapshot: the Free Company Data Product is a direct download without registration. Only the Companies House API requires a user account and an API key for every request.

As of 4 November 2026. Counts from the Companies House snapshot BasicCompanyDataAsOneFile-2026-11-01, counted by firmdat.co.uk. This article is general information and does not replace legal advice in an individual case.