How to find a company registration number
The company registration number (CRN) is a company’s permanent ID — the single most reliable way to look it up. Here’s what it is, what it looks like, and the quickest places to find one.
What a company number is
When a company is incorporated, Companies House assigns it a unique 8-character registration number. Crucially, it never changes — a company can rebrand and change its name many times, but its number stays the same. That’s why the number, not the name, is the dependable way to identify a company.
- England & Wales: 8 digits — e.g.
09876543. - Scotland:
SC+ 6 digits — e.g.SC123456. - Northern Ireland:
NI+ 6 digits — e.g.NI123456. - LLPs use an
OCprefix; a few older/special types use others.
Where to find it
- Search by name — the quickest way. Look the company up on Verivello or Companies House and the number is on its record.
- The company’s website footer — UK companies must display their number, usually near the registered office.
- Invoices, letterheads and terms — it’s legally required on business documents.
Why it matters
Because the number is permanent and unique, using it — rather than the name — avoids mixing up similarly-named companies, and lets you follow a company even after a rebrand. A business that claims to be a limited company but shows no registration number anywhere is worth a second look.
Frequently asked questions
What is a company registration number?
A company registration number (CRN) is the unique 8-character code that Companies House gives every UK company when it’s incorporated — for example 12345678. It never changes, even if the company changes its name, which makes it the most reliable way to identify and look up a company.
How do I find a company’s registration number?
The fastest way is to search Companies House (or Verivello) by the company’s name — the CRN is shown on its record. You’ll also find it printed on the company’s official documents: invoices, letterheads, its website footer, and its terms and conditions, because UK companies are legally required to display it.
What does a UK company number look like?
It’s 8 characters. Companies registered in England & Wales are usually 8 digits (like 09876543). Companies registered in Scotland start with SC, and Northern Ireland with NI, followed by 6 digits (like SC123456 or NI123456). Other prefixes exist for LLPs (OC), and older or special company types.
Is a company number the same as a VAT number?
No. A company registration number identifies the company at Companies House and every company has one. A VAT number is separate, issued by HMRC, and only companies registered for VAT have one (it looks like GB followed by 9 digits). They are not interchangeable.
Do sole traders have a company registration number?
No. Sole traders are not registered at Companies House, so they don’t have a company registration number — only registered companies (and LLPs) do. A sole trader deals with HMRC directly and has a UTR (Unique Taxpayer Reference) instead.
Where is the company number on an invoice?
By law, a UK limited company must show its registered company number on its business letters, order forms and website — most commonly in the footer, near the registered office address, or in the small print of an invoice or its terms. If a business claims to be a limited company but shows no number anywhere, treat that as a warning sign.