A Guide To The Company Registration Number (CRN) In The UK

What is a Company Registration Number (CRN)?

A company registration number – sometimes shortened to CRN number – is a unique identifier assigned to every registered company in the United Kingdom. 

It consists of an eight-character code that helps identify and verify the existence of a company registered with Companies House.

Your CRN is issued automatically when your company is incorporated, whether through Companies House directly or via a formation agent. 

It remains the same for the life of the company—even if the company changes its name or registered office.

If you want to register a company in the UK, you can use our free all-in-one company formation service and get your CRN number and your business banking and accounting sorted simultaneously.

What Does a UK CRN Look Like (Company Registration Number Examples)?

A UK CRN typically consists of 8 characters—either all digits or a combination of letters and numbers, depending on the type and location of the company. 

Below is a breakdown of the format based on jurisdiction (company registration number examples):

Who receives a CRN?

CRNs are assigned to all types of incorporated entities in the UK, including:

A CRN is not required for sole traders or general partnerships, as these business structures are not incorporated through Companies House.

Tip: If you're registering a company in the UK, our free all-in-one company formation service helps you secure your CRN while also setting up your business bank account and accounting tools in one simple step.

Why is a CRN Important?

Your company registration number plays a vital role in your business's legal identity. Here’s what it’s used for:

Changing Company Details: You’ll need to provide your CRN to make any changes through Companies House, such as updating your registered address or appointing a new director.

Where to Find Your CRN?

You can find your company registration number in several places:

If you’ve lost or forgotten your CRN, the easiest way to find it is through the Companies House search tool.

How to Find Your CRN in the Certificate of Incorporation?

The CRN number can be found on your certificate of incorporation which you will receive right after registering your business on Companies House.

Example of the Certificate of Incorporation with Company Number (CRN)

If you can’t find this document, you can look it up online on the Companies House page.

Example of a CRN shown on Companies House website

How Do I Find a Company Number (CRN) on Companies House?

The Companies House website is a great free resource that is easy to use and contains useful information.

To find the CRN you’re looking for you should follow this step-by-step process:

When Do I Need My Company Registration Number?

You’ll need to provide your CRN when:

Your CRN is essential for all official company activities. Think of it as the business equivalent of a personal ID number.

Is a CRN the Same as a Company Tax Number?

No. Your CRN is different from your Unique Taxpayer Reference (UTR) and VAT Registration Number.

Each serves a different purpose and is used in different contexts. It’s important not to confuse them.

What Happens if My CRN Is Entered Incorrectly?

If your CRN is mistyped or used incorrectly—such as on contracts, invoices, or government filings—it could cause:

Note: Make sure to always double-check your CRN when adding it to documents or digital forms.

Can I Change My Company Registration Number?

No. Your CRN is permanent and cannot be changed, even if:

If you close your company and incorporate a new one, the new business will receive a different CRN.

What Are CRNs Often Confused With?

It’s not uncommon for a CRN to be confused with other numbers and identifiers linked to company formation, taxation and administration. The most common examples are:

1. VAT number

If your business exceeds the VAT registration income threshold you will have to register for VAT. However, anyone can register for a VAT number in the UK, which is a nine-digit number that begins with the prefix ‘GB’ in Great Britain and ‘XI’ in Northern Ireland.

2. Unique Taxpayer Reference (UTR)

A Unique Taxpayer Reference (UTR) number is a 10-digit code assigned by HMRC to identify individuals and organisations within the UK tax system.

3. Employer Reference Number

An Employee Reference Number (ERN) is a unique identifier assigned to employers by HMRC. It consists of a combination of letters and numbers used to identify an employer's Pay As You Earn (PAYE) registration.

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ANNA makes company formation in the UK simple.

Once you form a company with us, we take care of everything—from registering your business and issuing your CRN to setting up your business bank account and accounting software. 

ANNA helps you register a UK company for free and open a business current account quickly, complete with a debit card to handle transactions effortlessly. 

Our all-in-one platform is designed for UK entrepreneurs who want to get started quickly and stay compliant with minimal hassle.

Whether you’re paying contractors, ordering supplies, or settling overheads, ANNA provides you with a streamlined banking experience at your fingertips.

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FAQ

Do I need a Company Registration Number?

Yes you do. If you’re an incorporated company in the UK, you need a CRN to perform vital business functions such as registering for VAT and opening a bank account.

Is a company registration number the same as a company name?

No. A company name is your business’s trading identity, while the company registration number (CRN) is a unique identifier issued by Companies House. The CRN doesn’t change, even if your company name does.

How do I get a company registration number for a new business in the UK?

To get your company registration number, you need to incorporate your business with Companies House, which involves the completion of various documents. Alternatively, you can register your company with ANNA for free, get a business account right away and become compliant with HMRC from day 1. 

Do sole traders have a company registration number?

No. Sole traders are not incorporated and do not register with Companies House, so they do not receive a CRN. Only incorporated entities like Ltds and LLPs are issued a CRN.

Sole traders aren’t legal companies; they’re self-employed individuals who operate businesses such as market stalls, taxi driving services and mobile hairdressers. 

If you’re a sole trader, you’re not compelled to register a company. 

Instead, you should register for Self Assessment and file your tax returns as a private individual.

How long does it take to receive a company registration number?

If you register online using Companies House or a formation service, you’ll typically receive your CRN within a few hours. Paper applications can take 8 to 10 days.

Do I need to display my CRN anywhere?

Yes. By law, your CRN must appear on:

This ensures transparency and legal compliance under the Companies Act 2006.

Can I use my CRN to check if a company is genuine?

Yes. You can use any CRN to look up a business on the Companies House register to verify its legal status, incorporation date, directors, and filing history.

What happens to my CRN if my company is dissolved?

Once a company is dissolved, its CRN becomes inactive. If you form a new company—even with the same name—it will be issued a new and separate CRN.

What is a Companies House authentication code?

It’s a private 6-digit code used to log in to the Companies House WebFiling service. Unlike your CRN, this should not be shared.

What is the difference between a CRN and a UTR number?

A CRN is a company registration number assigned by Companies House. A UTR number is a tax registration identifier assigned by HMRC.

What’s the difference between a CRN and a Company House Authentication Code?

Can I search for a company by CRN only?

Yes. On the Companies House service, you can search using either the company name or the CRN to view public records and filings.

Will I Get a New CRN if I Change My Company Name?

No. Your CRN remains the same regardless of a name change, address update, or director swap. It’s permanent. You will only receive a new CRN if you dissolve your company and form a new one.

Who needs a company registration number?

All incorporated businesses—including Ltds, PLCs, LLPs, and CICs—must have a CRN. It's issued during company formation.

How does a CRN relate to company tax and VAT?

You will need to provide your CRN to register for company taxes and VAT with HMRC.

Is a CRN required for international businesses operating in the UK?

Yes, every limited company from abroad that wants to set up a business base in the UK must have a company registration number. However, if you’re simply exporting goods or services in the UK with no headquarters in the country, you don’t need a CRN.

Our final word on CRNs…

As you can see, your CRN is vitally important to the security and operations of your business, so keep it accessible at all times. The best way to obtain and manage your CRN effectively is through a company formation specialist such as ANNA. Get your company registration number quickly by contacting us today to register your UK company.

Have a name for you new business yet?

Check it in our free company name checker – then proceed to register the company when you're ready.

Sources:

https://www.gov.uk/find-utr-number