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How this site counts

Everything here comes from two free public sources, and both are linked below so you can redo the work. If a number on this site is wrong, this page should be enough to prove it.

Where the data comes from

1. The free company data product

Companies House publishes the whole register once a month as a single compressed CSV, the free company data product. The snapshot used here is dated 2026-09-01 and contains 5,689,367 companies.

The filter is one condition: the CompanyCategory field contains "Public Limited Company". That returns 4,506 rows, and those rows are this website. Nothing is sampled, nothing is excluded for being small or obscure, and the dissolved and the failing are kept in, because knowing a PLC has gone is as useful as knowing it exists.

2. The official ten-year series

The trend on the front page is not ours. It is Table A3 of Companies register activities, the Companies House statistical release, published as an ODS spreadsheet attached to the release. We read it, converted it and republished it as a CSV because a table nobody can open is a table nobody quotes.

Effective register, total register

This trips up almost everyone who tries to count. Companies House reports the effective register, which excludes companies in liquidation or in the course of dissolution. The total register includes them. The two differ by several hundred companies, so quoting one against the other produces an argument where there is no disagreement.

Seventeen months separate those two snapshots, and over a decade in which the register has lost PLCs every year, a fall from 4,973 to 4,506 is what the trend predicts. Two sources, two methods, no contradiction.

The judgement calls

Three, and they are the only ones.

• Distress. "In trouble" on this site means a register status other than Active: liquidation, administration, receivership, or a proposal to strike off. Companies House uses a narrower definition for its effective register, which is why both numbers are shown rather than one.
• The five company threshold. Industry and location pages are built where at least five PLCs share a classification or a town: 149 industries and 100 places. Below five, a page tells you nothing you could not read off the list, and it identifies individual companies by address.
• Names. The register shouts every company name in capitals. We convert to title case for readability and keep the raw form in the download, so a name is never altered in the data itself.

What this data cannot tell you

Worth being blunt about, because the limits are structural and no amount of processing fixes them.

• Companies House does not verify what is filed with it. An address, a SIC code or a name is what somebody typed. It is a record of what was claimed, not a finding of fact.
• A registered office is an address for service. It is often an accountant, a law firm or a formations agent. It is not where the business operates, which is why London holds 2,156 of them.
• SIC codes are self selected, capped at four per company, and never audited. They are a reasonable guide in bulk and unreliable one company at a time.
• There are no financials here. The bulk register carries filing dates, not accounts. A company's turnover, profit and balance sheet are in its filed accounts on the Companies House service, linked from every company page.
• Nothing here says whether shares are traded. The register records the legal form, not a listing.

Corrections and licence

If something here is wrong, write to editor@publiclimitedcompany.co.uk with the company number and we will check it against the register and say what we changed. If the register itself is wrong about your company, we cannot fix that: the correction has to be filed with Companies House, and it will reach us at the next monthly snapshot.

Both source datasets are published under the Open Government Licence v3.0. The compiled tables and CSVs on this site are offered under the same terms: use them, republish them, credit them.