How the company rankings and statistics are produced
Where the figures come from, which companies are included, what a missing figure means, and the limits of data taken from accounts filed at Companies House.
Where the figures come from
Everything on the ranking and statistics pages comes from two public sources at Companies House:
- The company register: each company's name, number, status, registered office address, incorporation date and the industry (SIC) codes it has chosen.
- Annual accounts: the figures each company reports, such as net assets, cash at bank, average number of employees and, where given, turnover. Convert-IXBRL reads these from accounts filed in digital (iXBRL) form.
No figure is estimated, modelled or adjusted. A figure shown for a company is the figure in its filed accounts.
Which companies are included
- Active
- The company's status at Companies House is active. Dissolved companies are not in the data at all.
- Not dormant
- Rankings and financial statistics leave out dormant companies. Statistics pages show how many active companies are dormant.
- Recent accounts
- The company's latest accounts are made up to a date within 21 months of the newest accounts in the data. Each page states that date as "data as of".
- Enough companies
- A ranking is published only when at least 10 companies qualify. A statistics page needs at least 30 companies with recent accounts, and a median is shown only when at least 30 companies reported the figure.
What a missing figure means
These three cases are different, and the pages keep them apart:
- Not filed
- The company's accounts do not give the figure. Small companies and micro-entities may file a balance sheet without a profit and loss account, so most do not publish turnover or profit. Pages show "–". A company missing from a turnover list may still be large.
- Filed as zero
- The accounts state the figure as zero. It is shown as zero. For employees, a zero usually means the company has no staff apart from its directors, or did not state a number.
- Accounts that cannot be read
- Accounts filed on paper or as a scanned document carry no machine-readable figures. Many of the very largest companies file this way, so some well-known names do not appear in the rankings.
Because of this, a list of the largest companies by a figure is a list of the largest among companies that reported it in a readable form. Where only a minority report a figure, the page says how many did.
Location
A company is counted in a city when the post town of its registered office is that city. The registered office is a legal address and is not always where the company trades: many companies register at their accountant's or a company formation agent's office. Ranking and statistics pages state how many of the companies shown are at an address shared by 50 or more companies. UK-wide pages include every company, wherever it is registered.
Industry
Industries are defined by SIC codes, and each page lists the codes it uses. Companies choose their own codes and can hold up to four, so a company may appear under an industry it no longer works in, be missing from one it does work in, or appear in more than one.
Checks on filed figures
Filed accounts sometimes contain errors, such as an amount in thousands entered as a headcount. Figures that cannot be right are left out of rankings and are counted on each page under "How this list was made". For example, an employee number above 100,000, one identical to the net assets figure, or one implying less than £5,000 of turnover per employee. Growth lists leave out net assets more than 50 times the year before and headcount more than 10 times the year before.
Medians and counts on statistics pages
Statistics pages give totals and medians only; they do not name companies. The median is the middle company: half report more and half report less. It is used instead of an average because a few very large companies would otherwise dominate. Every median is shown with the number of companies it is taken from, and it describes those companies, not the whole industry. Medians are published only for figures that most companies report: net assets, employees, cash at bank and fixed assets.
"Incorporated in" tables count companies formed in a year that are still active. Companies that have since closed are not in the data, so these are not the total numbers formed.
Updates
The pages are rebuilt when the underlying data is refreshed. Each page shows the date of the newest accounts it uses. A company's figures change only when it files new accounts, usually once a year.
Corrections
If a figure for your company looks wrong, it will normally match what was filed at Companies House; filing corrected accounts there will update it here. You can also contact us and we will check it.