Company Registration Number CRN in the UK

Table of Contents

What is the Company Registration Number?

A company registration number (CRN), also known as the company number or registration number is a company’s identification. It is used to identify and verify whether a company is registered with Companies House. The number is a unique combination of numbers, and letters in some cases, that is specific to every business registered in the UK. The CRN will usually fall into one of the following formats:

  • Eight numbers: e.g. 12345678 or;
  • Two letters followed by six numbers: e.g. AB123456

When you’ve formed a company in the UK, it will be automatically assigned with the CRN by Companies House. As a CRN only applies to businesses incorporated or registered at Companies House, sole traders do not have company registration numbers as they are effectively one with their business.

The company registration number is generated automatically by the computer. Therefore, it cannot be changed or personally selected.

How is the Company Registration Number formatted?

A typical CRN comprises eight digits (numbers) or in some cases, consists of two letters followed by six digits. The exact mix is determined by the company’s structure and location.
Here are several examples of what your CRN might look like based on different scenarios in the UK:

England & Wales, or Wales only

  • Limited company: 01234567
  • Limited liability partnership: OC123456
  • Limited partnership: LP123456

Northern Ireland

  • Limited company (post-partition): NI123456
  • Older (pre-partition) company: R0123456
  • Limited liability partnership: NC123456
  • Limited partnership: NL123456


  • Limited company: SC123456
  • Limited liability partnership: SO123456
  • Limited partnership: SL123456

Please note that these are for illustrative purposes. The actual CRN for your company will be uniquely assigned by Companies House upon successful registration.

Where can I find my CRN number?

There are several ways to check your company registration number, including:

Incorporation Certificate from Companies House: When submitting an application to form a company and it’s approved by Companies House, an incorporation certificate is granted to you by Companies House. This is essential proof of registration compliance. Your company name and number will be featured on that.

Letters from Companies House to your company: Any official mail sent from Companies House to you will indicate your company registration number.

The UK government website: Don’t have a physical copy of the certificate with you at the moment? No worries, access the system of the UK Government, type your company name in the search box and there it is, your company details.

Your company formation service: If you’re having a service provider or an agency help you with company formation such as BBCIncorp, they will be able to give you your CRN.

In what situation is the Company Registration Number needed?

Since CRN helps identify a company, it needs to be provided on a wide range of occasions. As such, you will need to reference your company registration number when doing any of the activities below:

With Companies House

  • Changing the company name OR company’s registered office address
  • Changing the setting up or changing a Single Alternative Inspection Location (SAIL) address
  • Changing the location of statutory records between the registered office and the SAIL address
  • Appointing OR removing OR changing the details of a company director, company secretary or limited liability partnership (LLP) member
  • Filing a confirmation statement
  • Filing the company’s annual accounts
  • Filing copies of resolutions
  • Allotting shares or making other changes to the company’s share capital
  • Changing the company’s accounting reference date
  • Dissolving the company

Also, Companies House will request you to provide the company registration number if you make any enquiries.

Her Majesty’s Revenue and Customs (HMRC) enquiries

In a similar way, you will need to provide your CRN to HMRC when:

  • Activities related to corporation tax: registering for corporation tax, filing tax returns and paying tax
  • Activities related to VAT: registering the company for VAT, submitting VAT returns and paying VAT
  • Registering for PAYE and submitting PAYE reports
  • Filing company accounts
  • Informing HMRC that a new or existing company is dormant

When communicating to or making other enquiries to HMRC, bear in mind to always state your company registration number.

Other occasions

  • Communicating with government departments different from Companies House and HMRC
  • Opening a business bank account
  • Applying for other forms of credit
  • Issuing share certificates to shareholders OR dividend vouchers
  • Communication with shareholders or other parties about the company’s business

How to register for a Company Registration Number?

Your company registration number will be provided when you register your business with Companies House. To do this, there are a few things that you need to do including completing a series of documents, having your company name chosen and setting the UK address as your company’s registered office.

Memorandum Association documents are required to be filled with information such as all the names of company officers, directors and how share capital is divided between shareholders.

This may sound overwhelming so if you prefer to hand these paperwork to the professionals, finding an agent or a service provider like BBCIncorp to help you sort out the company formation is ideal. By doing this, you’re sure that the formation of your company is being taken good care of.

Where to put the company registration number?

According to the legal requirement from the UK government, businesses are required to display the company registration number on all business stationary. This includes, but is not limited to, the following:

  • Official company’s letterheads
  • Emails and email signature
  • Faxes
  • Invoices
  • Receipts
  • Order forms
  • Compliment slip
  • Leaflets, flyers and brochures
  • Catalogs
  • Websites and any other online material
  • Digital materials and collaterals
  • Advertisements
  • Other forms of printed marketing material

For additional information or inquiries, please contact us at We are here to assist you further.

Frequently Asked Questions

If I change my business name, will I receive a new registration number?

No. Your Company Registration Number remains the same if you change your company name. As such, in this case, there will be no changes to the CRN for the entire lifetime of the company.

In fact, you will simply receive a ‘certificate of incorporation on change of name’ from Companies House for this occasion. The previous and updated company names, date of the change will be displayed in this document alongside with the CRN.

Bear in mind that this certificate does not replace the original certificate of incorporation, so retaining both of these documents with company records is a must for any business.

What if I forgot my business registration number?

If you forget or lose your company registration number, don’t worry, you can find it in the aforementioned places, including:

  • Incorporation Certificate from Companies House
  • Official mail or letters from Companies House and HMRC
  • Online on the UK government website
  • Your company formation service

Is a CRN the same as a company tax number?

No. This is a common misconception, but a company registration number is NOT the same as a company tax number.

CRNs are issued by Companies House as a company’ identity whereas company tax numbers are unique 10-digit codes that are assigned by HMRC to track a company’s tax records.

Usually, a company tax number is referred to as a company’s Unique Taxpayer Reference (UTR) or simply ‘tax number’ or ‘tax reference’.

Do sole traders and partnerships need a CRN?

No. Since sole traders and ordinary (general) business partnerships are not required to register or incorporate at Companies House, they do not need a company registration number.

Disclaimer: While BBCIncorp strives to make the information on this website as timely and accurate as possible, the information itself is for reference purposes only. You should not substitute the information provided in this article for competent legal advice. Feel free to contact BBCIncorp’s customer services for advice on your specific cases.

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