United Kingdom · Companies House
UK Company Number Checker
Validate a Companies House company registration number (CRN) and see the registered company name, address and status.
What is a UK company registration number?
A UK company registration number (CRN) is the unique 8-character number Companies House allocates to every company, LLP and limited partnership on its register — for example 00445790 for Tesco PLC or SC045551 for a Scottish company. It never changes when the company changes its name or address.
UK company number format
Eight characters: eight digits, or a two-character register prefix plus six digits.
entity type (optional)
serial number
Examples: 00445790 (Tesco PLC, England & Wales) · SC045551 (NatWest Group plc, Scotland)
- 8 characters: Ordinary England & Wales companies have 8 digits; leading zeros count and must be entered. Scottish and Northern Irish companies, LLPs, limited partnerships and overseas companies use a 2-character prefix plus 6 digits.
- Common prefixes: SC Scotland, NI and R0 Northern Ireland, OC / SO / NC limited liability partnerships, LP / SL / NL limited partnerships, FC overseas company, BR UK establishment of an overseas company, OE overseas entity.
- No check digit: Companies House publishes no checksum, so a correctly shaped number can still be unregistered — only a register lookup proves it exists.
- Enter it as printed: Use upper-case letters and no spaces or GB prefix: a company number is not a VAT number. Jersey, Guernsey and Isle of Man companies are on their own registries, not Companies House.
How to check a UK company number
- 1 Find the number on the company’s letters, order forms, website or certificate of incorporation.
- 2 Enter all 8 characters above — pad short numbers with leading zeros and keep the letter prefix in capitals.
- 3 The checker confirms the format and looks the number up on the Companies House register, returning the company name, registered address and status.
- 4 Compare the returned company name, address and status with the business you are dealing with.
Frequently Asked Questions
How many digits is a UK company registration number?
Always 8 characters. Ordinary companies registered in England and Wales have 8 digits, such as 00445790 (Tesco PLC). Scottish and Northern Irish companies, LLPs, limited partnerships, overseas companies and some other entity types use a 2-character prefix followed by 6 digits, such as SC045551 (NatWest Group plc).
What does SC, NI or OC at the start of a company number mean?
The prefix shows the register and entity type: SC is a Scottish company, NI a Northern Ireland company, OC, SO and NC are limited liability partnerships in England & Wales, Scotland and Northern Ireland, LP, SL and NL are limited partnerships, and FC is an overseas company.
Is the company registration number the same as the UTR or VAT number?
No. Companies House issues the company number (8 characters). HMRC issues the Unique Taxpayer Reference (10 digits) and the VAT registration number (9 digits) — HMRC even asks for the company number and the UTR as separate items when a limited company registers for VAT. Check a UK VAT number.
Why does my company number only have 6 or 7 digits?
Older documents and software often drop the leading zeros. The zeros are part of the number: pad it on the left to 8 digits (445790 becomes 00445790) before checking — Companies House’s company pages and API need the full 8-character form.
Does a UK company number have a check digit?
No. Companies House publishes no check digit or checksum. A format check can only confirm the shape is right; only a register lookup proves the company exists, which is what the checker on this page does.
Where must a company show its registration number?
GOV.UK says a company must show its registered number on business letters, order forms and websites, together with its registered office address and where it is registered. It is also on the certificate of incorporation.
Last reviewed: , against official sources.
Verify UK companies at scale
Check company numbers and VAT numbers in one API call — with the registered name, address and status.