UK company number search

How UK company numbers work

A company registration number, sometimes called a CRN, is allocated on incorporation and never changes, even if the company later changes its name. It is never reused after a company is dissolved, so it remains a permanent identifier for that entity.

Most numbers are eight characters. Companies registered in England and Wales are usually all digits, Scottish numbers begin with SC, Northern Irish numbers begin with NI, and other prefixes exist for limited liability partnerships and other registered bodies.

• England and Wales: typically eight digits, often with leading zeros
• Scotland: SC followed by six digits
• Northern Ireland: NI followed by six digits
• Limited liability partnerships: OC, SO or NC prefixes
• Other prefixes exist for limited partnerships and specialist registrations

Where to find a company number

UK companies must state their registered name, number and registered office on their business letters, order forms and websites, so the number is usually easier to find than people expect.

• Invoices and receipts, where UK companies must state it
• Website footers, terms pages and privacy policies
• Letterheads, order forms and email signatures
• Contracts, engagement letters and tender documents
• Existing search results, where it appears beside the company name

What a number search shows you free

• Registered company name
• Company registration number
• Company status, such as active or dissolved
• Incorporation date
• Company type
• Jurisdiction
• Registered office address
• Previous company names
• Nature of business and SIC codes

Why search by number rather than name

• Names repeat: similar or identical names exist across different entities
• Names change: a rebrand leaves the number untouched
• Groups register multiple near-identical entities and only the number separates them
• Contracts and invoices are binding on the numbered entity, not the trading name

If the number does not match

Check for missing leading zeros and for a dropped SC or NI prefix, both of which are common transcription errors. Confirm you have not copied a VAT number, a charity number or a tax reference, which look similar but belong to different registers.

If the number still returns nothing, search by company name instead and compare the registered office address and incorporation date. If nothing matches at all, the business may be a sole trader or a partnership, which are not registered at Companies House.

Keeping a record of the entity

Once you have confirmed the number, the optional UK Company Information Report turns that entry into a dated PDF covering officers, persons with significant control, filing position and charges — useful when you want the numbered entity's details on file alongside a contract.

Free website search compared with the paid PDF report

Searching this site and viewing a company summary is free. The optional PDF report is paid, and what you are paying for is convenience: retrieval, formatting, a dated snapshot and a document you can download and keep. The underlying information is public and is also available directly from Companies House at no charge.

Frequently asked questions

Related pages

• UK Company SearchFree UK company search by name or company number. View company status, registered office, incorporation date, company type and SIC codes from the Companies House public register.
• Check Company StatusWhat UK company status values mean, including active, dissolved, liquidation, administration and proposal to strike off, and how to check the status of a company.
• Companies House SearchSearch company information from the Companies House public register by name or company number. Independent service with free company summaries and an optional formatted PDF report.
• UK Company ExtractWhat a UK company extract is, what an independently prepared PDF of public register information contains, and how it differs from an official certified Companies House document.
• UK Company Information ReportSee exactly what the UK Company Information Report contains, how it compares with the free company summary, and when a dated downloadable PDF of register information is worth ordering.
• Sample Company ReportSee the structure of the UK Company Information Report PDF section by section, page by page, so you know exactly what you receive before you order one.
• Company Number LookupLook up a UK company by its registration number. Understand CRN formats including SC, NI and OC prefixes, and confirm which company a number belongs to free of charge.