If you run a UK limited company, you will quickly encounter several identification numbers issued by different government departments. Three of the most important are your VAT number, company number and Unique Taxpayer Reference (UTR). Because all three identify your business in some way, it is easy to assume they are interchangeable. They are not.

Your company number identifies the legal company at Companies House. Your UTR identifies the company for Corporation Tax purposes with HM Revenue & Customs (HMRC). Your VAT number identifies a business that is registered for Value Added Tax.

Understanding the difference matters when opening business accounts, completing tax registrations, issuing invoices, filing returns, dealing with suppliers, or completing applications for financial services. This guide explains what each number means, when you receive it, where to find it, and which one you should use in different situations.

VAT Number vs Company Number vs UTR at a Glance

A company can have a company number and UTR without being VAT registered. A VAT number is only issued when the business is registered for VAT.

What Is a Company Number?

A Company Registration Number (CRN), commonly called a company number, is the unique identifier given to a company when it is incorporated or registered with Companies House. It identifies the legal entity itself. For example, if you incorporate a private limited company in England and Wales, Companies House assigns a company number to that company. The number remains associated with the company throughout its existence.

Companies House records can be searched using the company's name or company number. The public register provides information such as the company's registered office, status, directors, filing history and nature of business.

What does a UK company number look like?

Depending on where and how the company was registered, a company number may appear as:

• 12345678
• SC123456
• NI123456
• Other prefixes can apply depending on the company's jurisdiction and registration type.

Companies House describes a company registration number as usually consisting of eight numbers or two letters followed by six numbers, although formats can vary.

What is a company number used for?

You may need your company number when:

• Checking your company on Companies House
• Filing Companies House documents
• Updating company information
• Completing certain government forms
• Dealing with banks or financial institutions
• Providing evidence of incorporation
• Identifying your company to professional advisers
• Completing some HMRC registrations

Your company number is therefore fundamentally a corporate identity number, not a tax number.

What Is a UTR?

A Unique Taxpayer Reference (UTR) is a 10-digit number issued by HMRC for tax purposes. A limited company normally receives a Corporation Tax UTR when it is set up for tax purposes. HMRC describes the UTR as the company's tax reference and uses it to identify the company within its tax systems. For example, a company might have:

Company number: 12345678
Corporation Tax UTR: 1234567890

These numbers identify the same company, but they serve different purposes.

What is a company UTR used for?

Your Corporation Tax UTR can be required when:

• Dealing with HMRC about Corporation Tax
• Setting up Corporation Tax services in your business tax account
• Filing Corporation Tax information
• Authorising or working with a tax agent
• Completing certain HMRC registrations
• Corresponding with HMRC

HMRC states that a company's 10-digit UTR can be found on HMRC correspondence and Corporation Tax documents. When a company is registered with Companies House, its UTR is normally sent to the company's registered office address. GOV.UK states that if a company does not receive its UTR within the expected period, it can request the number from HMRC.

Is a UTR the same as a company number?

No. This is one of the most important distinctions to remember. The company number comes from Companies House and identifies the legal company. The UTR comes from HMRC and identifies the company's tax record. You should therefore not automatically enter your company number when a form specifically asks for your UTR.

What Is a VAT Number?

A VAT number, officially called a VAT registration number (VRN), is issued by HMRC when a business registers for VAT. Unlike a company number and Corporation Tax UTR, not every UK company will have a VAT number. A business generally becomes required to register for VAT when its taxable turnover exceeds the relevant VAT registration threshold, although voluntary registration is also possible in qualifying circumstances.

Once VAT registered, the business receives a VAT registration number and must follow the applicable VAT rules. GOV.UK's VAT registration process requires a limited company to provide information including its company registration number and UTR, which demonstrates that these are separate identifiers used during the same registration process.

What is a VAT number used for?

Your VAT number may appear on:

• VAT invoices
• VAT-related correspondence
• VAT returns
• Business records
• Certain commercial documents
• VAT verification processes

Customers and suppliers may also ask for your VAT number when they need to verify your VAT registration. GOV.UK provides a service that allows a UK VAT number to be checked for validity and confirms the business name and address associated with the number.

Does every limited company have a VAT number?

No. This is a common misconception. A company can be fully incorporated at Companies House, have a company number and have a Corporation Tax UTR while not being VAT registered. For example:

ABC Digital Ltd is incorporated in the UK. It has company number 12345678 and a Corporation Tax UTR. Its taxable turnover is below the compulsory VAT registration threshold and it has not voluntarily registered for VAT.

ABC Digital Ltd can legitimately operate without a VAT number.

The Key Difference Between the Three Numbers

The simplest way to understand the difference is to think about which government system the number belongs to and what it identifies.

Company number = legal identity

Your company number answers: “Which company is this?” It is the company's identity on the Companies House register.

UTR = tax identity

Your UTR answers: “Which taxpayer record does this company have with HMRC?” It is primarily associated with Corporation Tax and HMRC's tax systems.

VAT number = VAT identity

Your VAT number answers: “Which business is registered for VAT?” It identifies the business for VAT purposes. This distinction becomes particularly important for international founders who may encounter all three numbers when setting up banking, payment services, accounting systems and cross-border operations.

A Practical Example

Imagine that Global Commerce Ltd is incorporated in the UK. Companies House gives it:

Company number: 09876543

HMRC subsequently provides:

Corporation Tax UTR: 9876543210

Later, the company becomes VAT registered and receives: VAT number: 123456789, The three numbers belong to the same business, but they are not interchangeable.

The same company can therefore have several government-issued identifiers because different government systems perform different functions.

Can You Have a Company Number Without a VAT Number?

Yes. In fact, this is normal for many smaller companies. When a limited company is incorporated, it receives a company number. It also normally receives a Corporation Tax UTR through HMRC.

VAT registration is a separate matter. A business may choose to register voluntarily, or it may become legally required to register when it meets the relevant VAT conditions. This means the following combination is perfectly possible:

Company number: Yes
UTR: Yes
VAT number: No

A founder should not assume that a company needs to register for VAT simply because it has been incorporated.

Can a Company Have a VAT Number and UTR?

Yes. A VAT-registered limited company will normally have both. For example:

• Company number → identifies the company
• Corporation Tax UTR → identifies its Corporation Tax record
• VAT number → identifies its VAT registration

When registering a limited company for VAT, GOV.UK specifically asks for information including the company registration number and UTR. This is another reason why keeping your business records organised matters.

Which Number Should You Put on an Invoice?

It depends on the type of invoice. If your business is VAT registered, your VAT invoice must include the information required under VAT rules, including the relevant VAT registration details. Your VAT number is not simply a replacement for your company number.

For corporate identification, a business may also display its company registration details where required or appropriate. The important principle is to avoid treating your three identifiers as interchangeable simply because they all relate to the same business.

Where Can You Find Each Number?

Finding your company number

Your company number is available through the Companies House register. You can search for a company and view its public company information, including its registration number and status. Companies House provides access to this information free of charge. It can also appear on:

• Certificate of Incorporation
• Companies House correspondence
• Company documents
• Filing records

Finding your UTR

Your Corporation Tax UTR is normally found on HMRC correspondence and Corporation Tax documents. HMRC also provides an online process for companies that need to request their Corporation Tax UTR. Because your UTR is a tax identifier, it should be handled carefully and should not be confused with the publicly searchable company number.

Finding your VAT number

If you are VAT registered, your VAT number can usually be found on:

• VAT registration confirmation
• VAT invoices
• VAT returns
• HMRC VAT correspondence
• Your accounting records

You can also use the GOV.UK VAT verification service to check whether a known UK VAT number is valid.

Company Number vs UTR vs VAT Number for Global Founders

For non-UK residents establishing a UK company, these distinctions can become even more important. A founder may be asked for a “business registration number”, “tax identification number”, “VAT number” or “company number” by different providers. These terms should not automatically be treated as synonyms. For example, a payment provider might ask for a company registration number, while a tax service asks for a UTR and a supplier requests a VAT number.

If the business is not VAT registered, it should not invent or substitute a VAT number simply because an online form requires one. Instead, check whether the service provides an option such as “not VAT registered” or whether additional documentation is required.

This is particularly relevant to founders using UK company formation and management platforms such as IncorpUK, where company incorporation, tax administration and business infrastructure are separate stages of managing a UK company.

Why Mixing Up These Numbers Can Cause Problems

Using the wrong identifier can lead to unnecessary delays. For example, entering your company number into a field requesting a Corporation Tax UTR may prevent an application from matching your HMRC record. Similarly, entering a company number instead of a VAT number when a supplier is trying to verify your VAT registration may cause confusion. Before submitting a form, ask:

1. Who issued the number?
2. What does the form actually request?
3. Is the request about the company, Corporation Tax or VAT?
4. Is the business actually VAT registered?

These four questions solve most identification-number mix-ups.

Do Sole Traders Have These Numbers?

Not necessarily in the same combination. A sole trader does not have a Companies House company number simply because they are operating a business. They may have a Self Assessment UTR and, if VAT registered, a VAT registration number.

This is why it is important to distinguish between company identifiers and taxpayer identifiers. A limited company is a separate legal entity from its shareholders and directors, whereas a sole trader operates as an individual for legal and tax purposes. The terminology around UTRs can also vary because individuals, companies, partnerships and other entities can have different HMRC references.

A Simple Memory Trick

If you keep confusing the three, use this:

Company number → Companies House → Company

UTR → HMRC → Tax

VAT number → HMRC → VAT

Or remember:

Company number tells you who the company is. UTR tells HMRC who the taxpayer is. VAT number tells HMRC and other businesses that the business has a VAT registration.

That distinction is simple, but it prevents many administrative mistakes.

VAT Number vs Company Number vs UTR: Frequently Asked Questions

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

No. A VAT number identifies a business for VAT purposes, while the company registration number identifies the legal company registered with Companies House.

Is a UTR the same as a company number?

No. A UTR is an HMRC tax reference, while the company number is issued by Companies House.

Does every UK limited company have a UTR?

A limited company normally receives a Corporation Tax UTR when its Corporation Tax record is set up. HMRC describes this as a 10-digit reference used for the company's tax record.

Does every UK company have a VAT number?

No. A company only has a VAT number if it is registered for VAT.

Can I use my UTR instead of my VAT number?

Generally, no. They serve different purposes. If a form specifically requests a VAT registration number, use your VAT number if your business is VAT registered.

Where can I find my company number?

You can find it through the Companies House register and on company incorporation documents.

Where can I find my Corporation Tax UTR?

Your UTR is normally available on HMRC correspondence and Corporation Tax documents. If you have not received or cannot find it, HMRC provides a process for requesting it.

Can I check whether a VAT number is valid?

Yes. GOV.UK provides a VAT number verification service for checking the validity of a known UK VAT registration number.

Which number should I use when someone asks for my business registration number?

For a UK limited company, “business registration number” commonly refers to the company registration number/company number. However, terminology can vary between providers, so check the form's instructions before submitting the information.

Conclusion

Your company number, UTR and VAT number are three different business identifiers serving three different purposes. The company number comes from Companies House and identifies the legal company. The UTR comes from HMRC and identifies the company's tax record. The VAT number identifies a business that has been registered for Value Added Tax.

A UK limited company can therefore have a company number and UTR without having a VAT number. For founders, particularly those managing a UK company from overseas, keeping these identifiers clearly separated is more than an administrative detail. It helps prevent errors when dealing with Companies House, HMRC, banks, accountants, suppliers and payment providers. The easiest rule to remember is:

Company number = company identity.
UTR = tax identity.
VAT number = VAT identity.

Once you understand that distinction, most UK business registration and tax forms become considerably easier to navigate.