Short answer. Search the company name on the public register, then check the registered office and incorporation date against what you already know about the business. The registration number is the 8-character reference shown next to the company name.
What a company registration number looks like
A UK company registration number is 8 characters. Companies registered in England and Wales usually have 8 digits, often with leading zeros, such as 00445790. Companies registered elsewhere in the UK, and some legal forms, carry a two-letter prefix: SC for Scotland, NI for Northern Ireland, OC and SO for limited liability partnerships, and NC or FC for certain other registrations.
Leading zeros and letter prefixes are part of the number. Dropping them gives you a different company or no company at all.
Three ways to find it
- Search by name. Use our company search or the official register. Company names are not unique over time, so confirm the match rather than picking the first result.
- Look at company documents. Limited companies must show their registered name and number on letters, order forms, invoices and their website. The footer of a website and the bottom of an invoice are the most common places.
- Check filed paperwork. Accounts, confirmation statements and incorporation documents all carry the number.
How to confirm you have the right company
Similar names are common, and groups often register several companies with near-identical names. Before you rely on a number, compare at least two facts: the registered office address and the incorporation date. If a business has recently changed its name, the register records the previous name, which is a useful confirmation.
What the number is not
A company registration number is not a VAT number and not a tax reference. It is not evidence that a company is trading, solvent or reputable. It identifies the registered legal entity, nothing more. See company number vs VAT number vs UTR.
If you cannot find the company
Sole traders and ordinary partnerships are not registered at Companies House, so they have no company number. Some businesses trade under a name that differs from the registered company name; in that case search for the legal entity rather than the brand. Dissolved companies remain searchable on the official register.
This guide is general information about public company records, not legal, tax or financial advice. Independent service. Not affiliated with Companies House or GOV.UK.