How to Get a UK Business Registration Number

A Company Registration Number (CRN) is a unique identifier assigned to your business when you register with Companies House in the UK. This guide will walk you through the process of obtaining your CRN in 2025.

What is a CRN?

An 8-character code (numbers or 2 letters + 6 numbers) that uniquely identifies your company in the UK.

Who needs one?

Limited companies and LLPs – not required for sole traders or general partnerships.

Processing time

24 hours for online applications (standard service).

Step-by-Step Registration Process

Step 1: Choose Your Company Structure

Decide whether to register as a private limited company (Ltd), limited liability partnership (LLP), or another business structure. If you’re starting a cleaning business, a limited company (Ltd) is likely the best choice.

The key difference between a sole trader and a Ltd company is that sole traders are personally liable for business debts, while Ltd company owners have liability limited to their investment.

Step 2: Check Company Name Availability

Before registering, check if your chosen company name is available using the Companies House name availability checker.

Check Company Name

Step 3: Prepare Required Documents

You’ll need:

– Memorandum of Association (confirms company formation)
– Articles of Association (company rules)
– Details of directors and shareholders
– Registered office address in the UK
– SIC code (Standard Industrial Classification – describes your business activity)

Step 4: Register Online with Companies House

The fastest and most affordable way is to complete the online application directly on the Companies House website.

Step 5: Receive Your CRN

After successful registration, you’ll receive:

– A Certificate of Incorporation
– Your unique Company Registration Number (CRN)
– Confirmation of the company’s formation date

Pro Tip: Finding Your CRN

If you’ve already registered but can’t find your CRN, check:

– Your Certificate of Incorporation
– Official correspondence from Companies House
– The Companies House website by searching your company name

Find Your CRN

Frequently Asked Questions

Can I choose my own CRN?

No, your CRN is automatically assigned by Companies House and cannot be changed or customized.

Does my CRN change if I rename my company?

No, your CRN remains the same for the life of your company, even if you change its name, address, or directors.

What is the main difference between a sole trader and a limited company?

The key difference between a sole trader and a Ltd company is that sole traders are personally liable for business debts, while Ltd company owners have liability limited to their investment.

What’s the difference between a CRN and UTR?

A CRN is issued by Companies House for company identification, while a UTR (Unique Taxpayer Reference) is a 10-digit number issued by HMRC for tax purposes.