A company number is the unique eight-character identifier Companies House assigns at incorporation, which never changes for the life of the company.
It survives a change of name, a change of address, a change of every director and shareholder. Scottish companies carry an SC prefix and Northern Irish ones NI, which is why the number quietly tells you where a company was registered. Quote it, not the name, whenever precision matters — names are reused, numbers are not.
Related terms
- Companies House — Companies House is the UK registrar of companies: it incorporates companies, holds the public register of them, and receives their statutory filings.
- Certificate of incorporation — A certificate of incorporation is the document Companies House issues to confirm a company legally exists, showing its name, number and date of incorporation.
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Statutory rules, then the Companies House register. Free, and no email required.
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