Business Tax Reference Number: Complete UK Guide For 2026

A business tax reference number is an identifying number used by HM Revenue and Customs to connect a person or business with the correct tax account.

In many cases, people using this term mean a 10-digit Unique Taxpayer Reference, commonly called a UTR.

However, there is no single universal tax number that every UK business uses for everything.

A sole trader may have a Self Assessment UTR, while a limited company has its own Corporation Tax UTR. Businesses registered for VAT or PAYE receive additional reference numbers.

The correct number therefore depends on the business structure, the taxes it is registered for and what it is trying to do with HMRC.

How Have Business Tax Reference Numbers Changed In 2026?

The basic purpose and format of the main UK business tax reference numbers have not been replaced in 2026. A UTR is still normally a 10-digit number used by HMRC to identify the relevant taxpayer or organisation.

What has changed is the wider digital tax system surrounding these references. From 6 April 2026, Making Tax Digital for Income Tax became mandatory for certain sole traders and landlords with qualifying income above £50,000.

Affected taxpayers must keep appropriate digital records and use compatible software to provide information to HMRC.

The threshold is scheduled to extend to qualifying income above £30,000 from April 2027 and above £20,000 from April 2028.

This does not mean businesses receive a new type of UTR because of Making Tax Digital. Existing tax identifiers continue to be important for connecting taxpayers with the correct HMRC records and services.

The VAT registration threshold for 2026/27 also remains £90,000 of taxable turnover. Businesses must continue to monitor their taxable turnover to determine when VAT registration becomes compulsory.

For businesses, the main change in 2026 is therefore not a replacement of tax reference numbers, but the increasing importance of linking the correct reference with digital records, tax accounts, software and HMRC reporting obligations.

Why Are Tax Reference Numbers Required For UK Businesses?

Tax reference numbers allow HMRC to distinguish one taxpayer or tax account from another.

A reference becomes necessary when a person or business enters a tax system that requires HMRC registration. It allows tax returns, payments and correspondence to be allocated to the correct account.

For example, HMRC needs to distinguish between:

• A Sole Trader Paying Income Tax Through Self Assessment
• A Limited Company Paying Corporation Tax
• A Partnership Submitting A Partnership Return
• A VAT-Registered Business Submitting VAT Returns
• An Employer Reporting PAYE And National Insurance

A tax reference does not automatically mean that tax is due. It identifies the relevant account so HMRC can administer the tax correctly.

Businesses can therefore have several references at the same time because Corporation Tax, VAT, PAYE and Self Assessment operate as separate tax systems.

When Does A Business Need A Tax Reference Number?

The point at which a business needs a tax reference depends on its legal structure and activities.

A sole trader does not necessarily receive a UTR on the first day they start selling goods or services.

Registration for Self Assessment is generally required where gross trading income exceeds £1,000 during the tax year, although there are other circumstances in which registration may also be necessary.

Someone who needs to submit a Self Assessment return for the previous tax year will generally need to notify HMRC by 5 October.

A limited company will usually be set up for Corporation Tax when it is incorporated, unless it is dormant. HMRC issues the company with its own 10-digit UTR.

When the company starts doing business, Corporation Tax services need to be available through its business tax account.

Activities indicating that a company has started doing business can include:

• Buying Or Selling Goods
• Advertising The Business
• Renting Property
• Employing Someone
• Providing Services To Customers

A business will need a VAT registration number if it becomes liable to register for VAT. In 2026/27, compulsory VAT registration generally applies when taxable turnover exceeds £90,000 or the business expects to exceed the threshold within the relevant period.

A business becoming an employer will normally need to register with HMRC before its first payday so that it can receive an employer PAYE reference.

There is therefore no single point when every business must obtain every tax reference. Each reference becomes relevant when the business enters the tax regime connected with it.

Which Business Tax Reference Number Do You Need?

Businesses should first identify what tax or HMRC service they are dealing with before looking for a reference number.

Unique Taxpayer Reference

A UTR normally contains 10 digits. Individuals usually receive one when they register for Self Assessment.

A sole trader’s UTR belongs to the individual rather than being a general registration number for the trading name.

Corporation Tax UTR

A limited company normally receives its own 10-digit Corporation Tax UTR.

This reference belongs to the company as a separate legal entity. A director’s personal Self Assessment UTR should not be substituted for the company’s Corporation Tax UTR.

Partnership UTR

A partnership can have its own UTR for its partnership tax return.

Individual partners can also have personal UTRs for their individual Self Assessment obligations, meaning several UTRs may be connected with the same partnership.

VAT Registration Number

A VAT registration number normally contains nine digits and is issued when HMRC approves a VAT registration.

It is different from a UTR and is used for VAT administration, VAT returns and VAT invoices.

PAYE Employer Reference

An employer PAYE reference is issued when a business registers as an employer.

It is used when operating payroll and reporting information about employees to HMRC.

Accounts Office Reference

Employers normally also receive an Accounts Office reference. It contains 13 characters and is particularly important when identifying PAYE and National Insurance payments.

The PAYE employer reference and Accounts Office reference should not be treated as interchangeable.

A company may also have a Companies House registration number. This identifies the legal company but is not an HMRC tax reference.

How Can A Sole Trader Find Their UTR?

A sole trader normally uses their personal Self Assessment UTR rather than receiving a separate UTR for their business name.

The number can commonly be found in:

• The Personal Tax Account
• The HMRC App
• Previous Self Assessment Tax Returns
• HMRC Notices To File A Return
• Tax Calculations
• HMRC Payment Reminders
• Previous HMRC Correspondence
• Records Held By An Accountant

The UTR normally contains 10 digits and may simply be described as a tax reference on some correspondence.

A National Insurance number should not be used instead of a UTR. HMRC may request both numbers in some situations, but they have different purposes.

How Can A Limited Company Find Its Corporation Tax UTR?

A limited company’s UTR belongs to the company rather than its directors or shareholders.

The Corporation Tax UTR can normally be found on:

• HMRC Corporation Tax Correspondence
• Previous Company Tax Returns
• Notices To Deliver A Company Tax Return
• Corporation Tax Reminders
• The Company’s HMRC Tax Records
• Information Held By The Company’s Accountant

HMRC normally sends Corporation Tax information to the company’s registered office.

A company that cannot locate its UTR can request the Corporation Tax UTR from HMRC. It is important to make sure the registered office held at Companies House is correct because replacement information may be sent there.

The UTR should not be confused with the company registration number shown on the Companies House register.

How Can A Partnership Find Its Tax Reference?

A business partnership normally has a UTR for the partnership itself.

The nominated partner may be able to locate it through:

• Partnership Registration Records
• Previous Partnership Tax Returns
• HMRC Correspondence
• Tax Reminders And Statements
• Records Held By The Partnership’s Accountant

Individual partners may also have their own personal UTRs.

When completing returns, the partnership UTR should be used for the partnership’s tax affairs, while each partner uses their personal UTR for their own Self Assessment obligations.

Where Can A Business Find Its VAT Or PAYE Reference?

A VAT-registered business can normally find its VAT registration number on its VAT registration records, online VAT information, previous VAT returns and VAT invoices.

The number normally consists of nine digits.

Employers can usually locate their PAYE employer reference on:

• Employer Registration Information
• PAYE Correspondence From HMRC
• Payroll Records
• Payroll Software
• P60 Forms
• P45 Forms
• Records Held By A Payroll Provider Or Accountant

Businesses should also keep their Accounts Office reference available because it may be needed when making PAYE and National Insurance payments.

Business Tax Reference Number Vs Corporation Tax Payment Reference

One of the easiest mistakes for a limited company to make is assuming that its Corporation Tax UTR and Corporation Tax payment reference are the same number.

They are not.

A Corporation Tax UTR normally contains 10 digits and identifies the company within HMRC’s Corporation Tax system.

A Corporation Tax payment reference contains 17 characters and identifies the accounting period to which a Corporation Tax payment should be allocated.

The distinction is particularly important because the Corporation Tax payment reference changes for each accounting period.

For example, a company should not automatically reuse a Corporation Tax payment reference saved in online banking from a previous year without checking that it belongs to the accounting period being paid.

Using an incorrect payment reference could cause HMRC to allocate the money to the wrong tax period or another tax liability.

Businesses should therefore obtain the correct payment reference from the relevant Corporation Tax records or HMRC account before making a payment.

How Long Does It Take To Receive A UTR?

HMRC states that a UTR will usually arrive by post around 15 days after registration, although it can take longer for someone living overseas.

For a newly incorporated company, HMRC advises that a company can request its UTR if it has not received it after 15 working days.

The time required can vary depending on the circumstances and whether HMRC needs additional information.

Businesses waiting for a reference should avoid creating unnecessary duplicate registrations, as this can make tax records more difficult to resolve.

A newly registered business should also make sure the postal address supplied to HMRC or the registered office shown at Companies House is accurate.

What If A Business Has Not Received Or Has Lost Its Tax Reference?

The first step is to establish which tax reference is missing.

A business should not request a new UTR simply because it cannot find a VAT number, PAYE employer reference or Corporation Tax payment reference. These numbers belong to different tax records.

For a missing UTR, check existing HMRC correspondence, previous tax returns, online tax information and accountant records first.

Individuals and sole traders may also be able to find their UTR through their Personal Tax Account or the HMRC app.

A limited company that cannot find its Corporation Tax UTR can request it from HMRC. The replacement information is normally sent to the company’s registered address.

If a business has never received the number, it should also check whether the relevant tax registration has actually been completed.

What Happens If You Use The Wrong Tax Reference?

Using the wrong reference can prevent HMRC from correctly matching a return, registration or payment to the relevant tax account.

For example, problems can arise if a business:

• Uses A Company Registration Number Instead Of A Corporation Tax UTR
• Uses A Director’s Personal UTR For The Company
• Uses A Partnership UTR On An Individual Partner’s Return
• Uses A PAYE Employer Reference Instead Of An Accounts Office Reference
• Uses An Old Corporation Tax Payment Reference

The consequences depend on the transaction.

A payment made with an incorrect Corporation Tax reference may be delayed or allocated to a different liability. HMRC may then need to move the payment to the correct account or accounting period.

Businesses should therefore check both the name of the reference requested and its expected format before submitting information.

Does A Business Tax Reference Number Ever Change?

A UTR does not normally change every tax year.

A company’s Corporation Tax UTR generally remains attached to the company, while an individual’s Self Assessment UTR remains connected with that taxpayer.

Changing an accountant does not normally result in a new UTR. Similarly, changing a company name or registered office does not normally mean that the company receives a completely new Corporation Tax UTR.

However, not every HMRC reference is permanent.

A Corporation Tax payment reference changes for each accounting period. Businesses should therefore distinguish between the permanent tax identifier and references created for specific payments or periods.

A completely different legal entity will also normally have its own tax records. For example, forming a new limited company does not mean it can simply use the UTR of another company owned by the same person.

Do Dormant Companies Need A Tax Reference Number?

A new limited company that has not started trading may be treated as dormant for Corporation Tax.

A company can therefore exist legally at Companies House even though it is not currently carrying on business for Corporation Tax purposes.

Companies can still have Corporation Tax identifiers while dormant. In fact, a company telling HMRC that it is dormant may need its 10-digit UTR to complete the process.

After HMRC accepts that a company is dormant for Corporation Tax, it will normally not need to submit another Company Tax Return unless HMRC asks for one or the company starts trading again.

Dormancy does not remove Companies House obligations. A dormant company may still need to meet its separate company filing requirements.

When the company begins trading, it should ensure its Corporation Tax position is updated appropriately.

How Have Business Tax And Digital Reporting Rules Changed In 2026?

One of the biggest tax administration changes affecting smaller businesses in 2026 is the introduction of Making Tax Digital for Income Tax.

From 6 April 2026, the first mandatory group entered the system.

Sole traders and landlords with qualifying income above £50,000 for the relevant earlier tax year are required to follow Making Tax Digital for Income Tax unless an exemption applies.

Under the system, affected taxpayers generally need to:

• Maintain Suitable Digital Records
• Use Compatible Software
• Keep Their Business Information Up To Date
• Send Required Information To HMRC Digitally
• Complete Their Tax Reporting Obligations Through The MTD System

Further phases are planned.

Those with qualifying income above £30,000 are due to enter from April 2027, followed by those above £20,000 from April 2028.

Making Tax Digital does not replace the UTR.

Instead, the UTR continues to help identify the taxpayer while compatible software and digital records change how information is maintained and reported.

This distinction is important for businesses searching for a new “MTD tax reference number”. There is not a universal replacement tax number created simply because a taxpayer moves into Making Tax Digital.

For startups, the practical lesson in 2026 is to treat tax registration and digital record keeping as connected parts of the same compliance process.

Businesses should know which HMRC registrations apply to them, retain the correct references and make sure those details are available when setting up tax software or working with an accountant.

Conclusion

A business tax reference number is not one universal number shared across every type of UK business tax.

Sole traders generally use a personal Self Assessment UTR, limited companies have their own Corporation Tax UTR and partnerships can have a separate partnership UTR. VAT-registered businesses and employers receive additional VAT and PAYE references.

The point at which a business needs a particular reference depends on what the business does and which tax obligations apply.

VAT registration, employing staff, starting a company and becoming liable for Self Assessment can all create different registration requirements.

Businesses should also distinguish permanent identifiers such as a UTR from references used for particular purposes, especially the 17-character Corporation Tax payment reference.

With Making Tax Digital for Income Tax beginning for the first mandatory group in April 2026, maintaining accurate tax records and knowing which reference belongs to which HMRC account has become even more important.

Frequently Asked Questions

Is A Business Tax Reference Number The Same As A UTR?

Often, but not always. The phrase commonly refers to a UTR, although a business may also have VAT, PAYE and other tax-specific reference numbers.

Does Every UK Business Need A UTR?

Not every business needs the same UTR. Whether one is required depends on the business structure, income and the tax registrations that apply.

When Does A New Business Need A Tax Reference Number?

A reference becomes necessary when the business needs to register for the relevant tax, such as Self Assessment, Corporation Tax, VAT or PAYE.

Can A Business Start Trading Before Receiving Its UTR?

A business may begin trading before its UTR arrives, but this does not remove its responsibility to complete the required tax registrations and meet HMRC deadlines.

Is A Corporation Tax UTR The Same As A Corporation Tax Payment Reference?

No. A Corporation Tax UTR identifies the company, while the 17-character payment reference identifies the accounting period to which a Corporation Tax payment should be allocated.

Can I Find My Company UTR On Companies House?

No. Companies House displays the company registration number, but a company’s Corporation Tax UTR is an HMRC tax identifier and is not shown on the public Companies House register.

Does A Business Tax Reference Number Change Every Year?

A UTR normally remains the same rather than changing annually. However, some payment references, including the Corporation Tax payment reference, change between accounting periods.