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What Is a Tax Reference Number? All You Need To Know

Navigating the complex world of tax reference numbers can be daunting, but understanding their purpose and importance is crucial for managing your tax affairs efficiently. In this blog post, we’ll explore the different types of tax reference numbers, how to locate them, and the challenges of managing them when working for multiple employers or as a self-employed individual. We’ll also discuss the risks associated with losing your Tax Reference Number and offer tips for keeping them secure. So, let’s dive in and unravel the mystery of tax reference numbers to help you stay on top of your tax game.


Understanding Tax Reference Numbers

Tax reference numbers play a pivotal role in managing your tax code and assuring accurate tax reporting within the UK tax system. There are four primary types of tax reference numbers, which can be obtained through the tax office reference number:

  1. National Insurance Number

  2. Unique Taxpayer Reference (UTR)

  3. Employer PAYE Reference Number

  4. VAT Registration Number

Each of these reference numbers has a distinct role in the realm of income tax, underlining the importance of grasping their significance and their application in managing your tax affairs during a specific tax year.

The different reference numbers used in the UK for tax purposes are:

  • National Insurance Number: a personal identifier for individuals

  • UTR (Unique Taxpayer Reference): assigned to both individuals and businesses required to file a Self Assessment tax return

  • Employer PAYE Reference Number: assigned to companies

  • VAT Registration Number: used by businesses registered for VAT in the UK

Having a thorough understanding of these reference numbers allows you to meet your tax obligations more effectively and avoid potential issues with HMRC.

National Insurance Number

The National Insurance Number (NINO) is a unique identifier assigned to individuals in the UK for tax and social security purposes. Composed of letters and numbers, it remains unchanged throughout one’s lifetime and can be found on official documents such as payslips, P60s, and letters pertaining to tax. The primary purpose of a National Insurance Number is to guarantee that the National Insurance contributions or taxes paid are accurately documented on your HMRC record.

It is important to note that the NINO is not a form of identification but serves as a reference number in the Pay As You Earn (PAYE) system and for the self-employed. Maintaining a record of your National Insurance Number can help deter potential issues with your tax reporting and guarantee accurate allocation of your contributions and taxes.

Unique Taxpayer Reference (UTR)

A Unique Taxpayer Reference (UTR) is a 10-digit number assigned by HMRC to individuals and businesses required to submit a Self Assessment tax return. The UTR is an essential tax reference number that helps identify a particular employer or individual for tax purposes. It is used for filing company tax returns or an individual’s Self Assessment tax return.

To obtain a UTR, you must register for Self Assessment with HMRC. When submitting a Self Assessment tax return online, you’ll need your UTR and Government Gateway log-in details. Using your valid UTR number when filing your tax return is pivotal, as penalties may ensue from submitting an incorrect Self Assessment tax return.

Employer PAYE Reference Number

An Employer PAYE Reference Number is a unique identifier assigned to a company in the UK tax system. The code comprises of three digits. The remaining characters are a combination of alphanumeric. The first three digits indicate the relevant tax office responsible for the employer, enabling HMRC to identify the company for tax purposes and link employees’ National Insurance numbers to it.

Employer PAYE reference numbers and tax codes are used to ensure the accurate remuneration of employees. Keeping track of your Employer PAYE Reference Number is crucial, whether you are a business owner or an employee, to prevent any potential issues with employee tax reporting and deductions.

VAT Registration Number

A VAT Registration Number is a unique identifier assigned to a business or legal entity that is registered for Value Added Tax (VAT) in the UK. It is used for tax records, payment purposes, and accurately identifying the business for VAT-related transactions. The VAT Registration Number is comprised of three digits, followed by a combination of numbers, letters, or both.

The primary purpose of a VAT Registration Number is to:

  • Verify VAT charges on invoices

  • Maintain a record of the VAT Registration Number

  • Confirm the accuracy of the VAT Registration Number on all VAT invoices

  • Avoid potential discrepancies with VAT reporting and payments.

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Locating Your Tax Reference Numbers

With a deeper grasp of the different types of tax reference numbers, let’s delve into the process of locating them. Whether you need to find your:

  • National Insurance Number

  • UTR

  • Employer PAYE Reference Number

  • VAT Registration Number

It’s essential to know where to look. This can save you time and potential headaches when dealing with tax-related matters.

In the following subsections, we will provide guidance on how to locate each of these tax reference numbers on various documents and online platforms. These tips will equip you to manage your tax affairs more efficiently and assure accurate tax reporting.

Finding Your National Insurance Number

Locating your National Insurance Number is relatively straightforward, as it can be found on a variety of official documents. These include:

  • Payslips

  • Tax returns

  • PAYE coding notices

  • Letters from the Department for Work and Pensions (DWP)

  • Bank statements if you receive a pension

  • Letters concerning tax, pensions, and benefits

If you still cannot locate your National Insurance Number, you can contact the National Insurance numbers helpline for assistance. They can provide guidance on how to find your NINO or help you obtain a new one if necessary.

Obtaining Your UTR Number

Your UTR number is issued by HMRC and can be found on various documents such as:

  • your SA250 “welcome to self-assessment” letter

  • previous self-assessment tax returns

  • payment reminders

  • notice to file a tax return

  • statement of account

Additionally, you can find your UTR on your personal account on the HMRC website.

If you’re unable to locate your UTR number on any of these documents, you can contact HMRC directly to obtain it. Keep in mind, having your UTR number readily available is key when filing your Self Assessment tax return or addressing any tax-related matters.

Tracking Down Your Employer PAYE Reference Number

To find your Employer PAYE Reference Number, you can check payroll correspondence, such as P60 forms or payslips. If you’re a business owner, the Employer PAYE Reference Number can be found on any letter between HMRC and your business upon registration for PAYE or on a past or present employee’s P60 or P45 form.

In case you’re unable to locate your Employer PAYE Reference Number on these documents, you may need to contact your employer or HR department for assistance. Having this number readily available is imperative for accurate tax reporting and addressing any tax-related issues concerning your employment.

Verifying Your VAT Registration Number

Your VAT Registration Number can be located in the upper right corner of the letter received from HMRC after registering for VAT. If you need to verify a VAT Registration Number, you can use the VAT number checker provided by the government website of the respective country. In the UK, this service is available on the gov.uk website.

If you harbor any doubts about the validity of a VAT Registration Number, reaching out to the HMRC VAT helpline is recommended. They can access a database of VAT-registered businesses and verify the registration number for you.

Tax Reference Numbers for Multiple Employers and Self-Employment

Managing tax reference numbers becomes more challenging when working for multiple employers or as a self-employed individual. Under such circumstances, maintaining a record of each employer’s unique reference number and obtaining a UTR number for self-employment takes on added importance for ensuring accurate tax reporting and preventing potential issues with HMRC.

In the following subsections, we will discuss the challenges of managing tax reference numbers when working for multiple employers or as a self-employed individual and provide guidance on how to effectively handle these situations.

Juggling Multiple Employer Reference Numbers

When working for multiple employers, it is essential to keep track of each employer’s unique reference number to guarantee accurate tax reporting. Failing to do so can lead to incorrect tax reporting, which can incur fines and penalties. To maintain accurate records of each employer’s unique reference number, consider storing the reference number in a secure place, such as a password-protected file or a secure online storage system.

Additionally, it’s crucial to keep track of any changes to the reference number, such as when an employer updates their reference number. A systematic and diligent approach to your employer reference numbers will help avert potential tax-related issues and guarantee precise reporting of your income and tax deductions.

Navigating Tax Reference Numbers as a Self-Employed Individual

As a self-employed individual, obtaining a UTR number is essential for accurate tax reporting. Registering for Self Assessment with HMRC will provide you with a UTR number, which you’ll need for filing your Self Assessment tax return and dealing with other tax-related matters.

To ensure that you’re using the correct tax reference number when completing an online company tax return, refer to your UTR number, which is typically labeled as ‘UTR’, ‘tax reference’, or ‘Official Use’. Maintaining an organized and diligent approach to your UTR number can help ward off potential tax-related issues and ensure precise reporting of your self-employed income.

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Protecting Your Tax Reference Numbers

Given the importance of tax reference numbers in managing your tax affairs, safeguarding them from potential risks and unauthorized access is crucial. Losing your tax reference numbers can lead to issues such as:

  • Identity theft

  • Difficulty claiming benefits

  • Obtaining a student loan

  • Potential fines and penalties from HMRC

In the following subsections, we will discuss the risks associated with losing your tax reference numbers and offer tips for keeping them secure. Adopting necessary precautions can help you protect your financial and tax-related information, thereby preventing potential issues.

The Risks of Losing Your Tax Reference Numbers

Losing tax reference numbers can have several negative consequences, including:

  • Increased vulnerability to identity theft and fraud

  • Difficulty in filing tax returns

  • Inability to access tax-related services

  • Potential for errors in tax calculations

  • Difficulty in resolving tax-related issues

For example, misplacing a UTR number could lead to a worst-case scenario of identity theft.

The potential risks associated with losing other tax reference numbers include incurring fines or penalties from HMRC, difficulty in filing tax returns, and difficulty in resolving tax-related issues. Hence, it is of utmost importance to diligently safeguard your tax reference numbers and have them readily available.

Tips for Keeping Your Tax Reference Numbers Secure

To ensure the security of your tax reference numbers, consider the following measures:

  • Store them in a secure online storage system or a locked filing cabinet

  • Exercise caution when providing your tax reference numbers to third parties

  • Only share them with reliable individuals or organizations

Regularly monitor your financial and tax-related accounts for suspicious activity or unauthorized access, including any unexpected tax refund notifications. Be wary of any phishing attempts or fraudulent communications requesting your tax reference number. Before disclosing any information, verifying the authenticity of the request is crucial. By taking these precautions, you can protect your tax reference numbers and stay on top of your tax affairs.

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In conclusion, understanding and managing tax reference numbers are crucial aspects of navigating the UK tax system. By familiarizing yourself with the different types of tax reference numbers, locating them, and protecting them, you can ensure accurate tax reporting and avoid potential issues with HMRC. Whether you’re an employee, self-employed, or a business owner, staying organized and diligent with your tax reference numbers will help you stay on top of your tax game and ensure a smooth tax journey.

If you’re unsure about any aspect of your taxes or need assistance with financial tax planning, consulting tax advisors at Sleek will save you time, money, and potential headaches. At Sleek, we provide accounting services to aid you with an efficient and seamless tax process.


Your Unique Taxpayer Reference (UTR) number can be found in your Personal Tax Account, the HMRC app under ‘Your details’ or in the Self Assessment section. It is important to note that a tax reference number is not the same as a UTR and relates to different things, such as indicating which employer you are working for, which will appear on your paylip or letters from HMRC.


A PAYE reference number is a unique set of letters and numbers issued by HMRC which identifies an employer’s PAYE scheme. It consists of three digits indicating the responsible tax office followed by seven unique digits or letters associated with the company.


No, not everyone has a UTR number. It is only necessary for those who file Self-Assessment tax returns due to setting up a limited company or being self-employed.


You can locate your National Insurance Number on official documents such as payslips, P60s, and tax-related correspondence.

If you’ve lost your tax reference numbers, contact the respective authorities and take preventative measures to keep them secure in the future.

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