What is a Company Registration Number and How to Find It?

A company registration number (CRN) is issued by Companies House when a business is officially incorporated in the UK. It is used to identify your company in legal, tax, and regulatory contexts. Every limited company (Ltd), limited liability partnership (LLP), and other incorporated entity has a CRN. Sole traders and general partnerships do not, since they are not incorporated through Companies House.

You’ll use your CRN for tasks like filing annual returns, registering for VAT, opening a business bank account, or updating company details. Unlike your business name, the CRN remains fixed throughout your company’s life, even if you change directors, addresses, or the name itself.

Where to find your Company Registration Number

Every company incorporated in the UK has a CRN assigned at the moment of registration. In case you’ve lost track of your documents or simply don’t know where to look, here are all the ways you can locate it.

Certificate of Incorporation

The Certificate of Incorporation is one of the first documents issued to your company upon successful registration. It’s an official confirmation that your company exists as a legal entity.

Your CRN is shown clearly, usually beneath the company name and incorporation date. If you can't find a printed copy, try locating a scanned PDF version, which your accountant or formation agent may have provided.

If you formed your business years ago, check your digital or physical files – it’s likely saved there.

Companies House Public Register

The Companies House public register is the most direct and reliable method of locating your CRN. It’s an online database that contains up-to-date details on every company registered in the UK. 

The search function is free and open to the public, meaning anyone, whether a director, client, or supplier, can verify a CRN.

Official communications from Companies House

If you receive mail or email directly from Companies House, your CRN will always be included. You’ll find it in statutory letters, notices for confirmation statements, reminders for accounts deadlines, and similar correspondence. The CRN usually appears at the top of the letterhead or email, near the company name.

Change of Name Certificate

If your company has changed its name, you will have received a new certificate reflecting this change. 

Importantly, the CRN remains unchanged because it appears on both the original Certificate of Incorporation and the Change of Name Certificate. This ensures continuity and helps stakeholders recognise your company regardless of name changes.

Documents from your accountant or formation agent

Many businesses are formed through agents or accountants. These service providers typically send welcome packs that include essential company details. Your CRN is likely listed in these documents or in their client portal if they provided one. If you can't find it, request a copy or a login link from your agent.

How to find your CRN online

To retrieve your CRN quickly, follow this process:

This method is accessible to the public and is free to use.

CRN format differences across UK regions

The format of your company registration number depends on your business type and jurisdiction. 

These prefixes indicate the registration office and type of company. There are no tax or legal advantages tied to the CRN format. 

However, some legal and administrative procedures differ across jurisdictions, for example, court systems in Scotland vs. England.

Where are you legally required to display your CRN?

Under UK company law, all limited companies and LLPs must display their CRN on certain materials and platforms. These include:

Omitting your CRN from these materials is considered non-compliant.

What are penalties for not displaying your CRN

Displaying your company registration number is a legal requirement for incorporated businesses in the UK. It must appear on specific documents and platforms, including your website, invoices, letterheads, and official email correspondence. Failure to include your CRN where required is considered a breach of company law.

Financial penalties

Enforcement consequences

Does the CRN ever change?

No. Your CRN is permanent. It is tied to your company from the moment it is registered with Companies House. Even if you:

…the CRN remains the same. It serves as a fixed point of identification in all legal, tax, and administrative systems. You can close your company and register a new one, but that would be the only way to receive a new CRN.

Why the CRN is more than an identifier

Your CRN is required for daily business activities and has a crucial role in everything from ensuring legal compliance to securing funding. 

The CRN connects your business to every official record held by Companies House, HMRC, and other UK institutions. It is used to verify, track, and enforce your company's legal obligations. 

1. Confirms your company’s legal identity

When someone searches your business on the Companies House register, your CRN links them to the correct records. It shows that your company is incorporated, active, and listed under UK law.

2. Required for filings and applications

Companies must include their CRN when submitting confirmation statements, annual accounts, corporation tax returns, VAT registration, and more. Government systems rely on it to associate all filings with the correct entity.

3. Distinguishes similar business names

Many UK companies operate under names that are nearly identical. The CRN avoids confusion. Banks, suppliers, and clients use it to confirm they are dealing with the correct company.

4. Enables verification for grants and licensing

Regulators, grant bodies, and procurement frameworks often require a CRN as part of eligibility checks. Without it, your company may not be able to submit applications or qualify for certain programs.

5. Supports regulatory enforcement

The CRN allows Companies House and other authorities to monitor compliance. Missed filings, legal actions, or updates are all recorded under the CRN.

Want to Register a UK Company and Get Your CRN?

If you're starting a new business in the UK and need your company registration number (CRN), ANNA can help you take care of everything in one step, at no cost.

What you get with ANNA:

You can check if your company name is available, register online, and receive all the documents you need to start trading, without having to visit multiple services or pay separate fees.

Start your company formation today. It’s fast, free, and includes everything required to operate legally and professionally in the UK.

FAQ

What if I don’t have a CRN?

If you're a sole trader or part of a general partnership, you won’t have a CRN. These business types aren’t registered through Companies House.

Can I apply for a new CRN?

You can’t change your CRN. If you want a new one, you must close your current company and register a new entity.

What’s the quickest way to find my CRN?

Use the Companies House website. Enter your company name and view your CRN at the top of the company profile page.

Can I verify another company’s CRN?

Yes. Anyone can use the Companies House public register to check CRNs and ensure a business is registered and compliant.

Does CRN format affect tax status or legal protections?

No. The format reflects location and type, but not benefits or obligations. Any tax credits or legal protections come from your business structure and jurisdictional laws, not the CRN prefix.

Do I have to show my CRN online?

Yes. Your CRN must be visible on your company website. Hiding it or omitting it could lead to fines.