Tax Identification Numbers (TINs) in the UK

TIN stands for Tax Identification Number, and it is used for official purposes in managing various types of taxation. TIN is an American term, used by the IRS in the USA, but in the UK, the equivalent exists in other forms. In this blog article, we provide an overview of everything you need to know about TINs.

What is a UK tax identification number (TIN)?

In the UK, TINs (Tax Identification Numbers) are a string of random numbers and letters that are inked onto our payslips, P60s, and tax returns – hiding in plain sight.

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TINs don’t usually hold much significance to businesses in the UK, as HMRC and Companies House do not use the term TIN in any official financial capacity. However, it is a term that many countries do use, such as the US and the EU. Therefore, if you or your company operates in these regions for any reason, you’ll need to be familiar with TINs to do business abroad.

What are the UK equivalents of TINs?

In general, TINs are an umbrella term for various types of tax identification numbers. In the UK, these are:

Use case	UK identifier
Personal tax & benefits	National Insurance number (NINO)
Self-employed tax return	Unique Taxpayer Reference (UTR)
Company formation	Company Registration Number (CRN)
VAT reporting	VAT Registration Number
Payroll	PAYE Reference

These numbers will ensure that your exact limited company can be tracked for tax purposes.

UK TINs and overseas trade

While TINs are not an official term in the UK, they are very much a reality in other parts of the world – particularly in the US and the EU.

Some types of international TINs are:

• Social Security Number (SSN) – United States.
• Codice Fiscale – Italy.
• Business Number – Canada.
• Numer Identyfikacji Podatkowej (NIP) – Poland.

As a business owner, you may need to provide goods or services to other international markets. For instance, if you are self-employed and working with international contracts, you may need to provide your NINO or UTR to report foreign income on your Tax Return. Likewise, if you were a VAT-registered company, you would need to provide your VAT Registration number when producing invoices for foreign clients.

These may be referred to as TINs in your communication.

TINs for individuals vs businesses: What’s the difference?

TINs used by individuals, sole traders, and self-employed people differ from those used by limited companies.

For instance, while every person has a National Insurance number, only businesses need to register for a VAT registration number (and that’s only if their taxable turnover is above £90,000).

It is important to know this distinction when navigating the UK tax system. To speed things up, we’ve made a quick table.

National Insurance number: your personal tax ID

Most of us have been familiar with National Insurance numbers (NINOs) throughout our lifetimes. It is located in the top right of your payslips, in the middle of your P60s, on HMRC correspondence, and in your HMRC personal online account.

NINOs are represented by a 9-digit code consisting of 3 letters and 6 numbers, following this exemplar format: AB123456C.

Who uses National Insurance numbers?

Your NINO helps keep track of all of your personal tax information, from your tax records to your state benefits, which is valuable for many governmental and financial organisations.

Specifically, NINOs are used by:

• HMRC.
• Employers.
• Department of Work and Pensions.
• Local councils.
• Electoral Registration Office.
• Student Loan Company.
• Pension providers.
• Individual Savings Accounts (ISA) providers.
• Financial services providers.

If you can’t find your NINO, you can find it on HMRC’s website.

When does HMRC issue National Insurance numbers?

HMRC issues NINOs often before we even know they exist. That is because UK law stipulates that every UK resident automatically receives their National Insurance number 3 months before their 16th birthday, provided they:

• Live in the UK.
• Had a parent or guardian complete a Child Benefit claim form for them.

Your NINO is the same for life, so will not change, even if your personal details, such as your name, have been changed.

UTR: when you’ll need it

A UTR is a type of TIN used by anyone who files a personal or company tax return, from a freelance carpenter to an accounting firm, and can be distinguished as personal and company UTRs.

The code is 10-digits long and only features numbers. For example, 1234567890.

Personal UTRs

HMRC will issue UTRs to individuals who are registered for Self Assessment, meaning anyone with some form of self-employment income will need a UTR to complete their personal tax returns.

This includes:

• Sole traders.
• Freelancers.
• Company directors.
• Shareholders.
• Individuals who need to report and pay Capital Gains Tax.
• Individuals who need to pay the High Income Child Benefit Charge.
• Anyone who receives income from rent, savings, investments, foreign income, or tips and commission.

HMRC uses personal UTRs to track the tax owed by individuals who are self-employed or who earn money outside of payroll.

Company and partnership UTRs

When you register your company at Companies House, you are automatically allocated a company UTR. You need this code to complete many tasks required for the effective running of a limited company, such as:

• Registering for Corporation Tax.
• Filing Company Tax Returns and annual accounts with HMRC.
• Paying your Corporation Tax bill.
• Registering for Value Added Tax.
• Registering for PAYE.
• Updating business details.
• Changing your Corporation Tax accounting period.
• Making the company dormant for Corporation Tax.
• Corresponding with HMRC.

If you are in a partnership, you will need to provide your UTR when:

• Registering an LLP or LP for Self Assessment.
• Filing an annual Partnership Tax Return.
• Registering for VAT and PAYE.
• Notifying HMRC of certain partnership changes.
• Contacting HMRC about the partnership.

Make sure you have your details to hand, as they can be easily lost and can take some time to recover.

What happens if you lose your company or partnership UTR?

You can find your company or partnership UTR online by logging into your HMRC online business tax account. Like with a personal UTR, you can also find it on previous tax returns and HMRC correspondence.

You can also request a copy of your company’s UTR online by providing your company registration number and company name.

Company registration number (CRN): Proof of incorporation

Similar to a company UTR, a company registration number is assigned to you when your company is incorporated with Companies House. Unlike a UTR, a CRN is used for managing a company’s tax affairs rather than paying tax.

A CRN looks like an 8-digit code. It can consist of either eight numbers or two letters followed by six numbers (e.g. 12345678, AB123456).

When do you need to use your company registration number?

There are many common reasons for a CRN code throughout your company’s life. You will need a CRN for:

• Filing an annual confirmation statement with Companies House.
• Submitting annual accounts to Companies House and HMRC.
• Registering for Corporation Tax.
• Filing a Company Tax Return or Partnership Tax Return.
• Paying your Corporation Tax bill.
• Registering for VAT and PAYE.
• Filing VAT Returns and PAYE reports.
• Updating company details with Companies House, including a change of registered office address or a change of company/LLP name.
• Filing a Return of Allotment of Shares.
• Issuing share certificates.
• Appointing and removing company directors and secretaries.
• Opening business bank accounts in the company name.
• Applying for business loans or credit.
• Setting up accounts with suppliers.
• Ordering or creating business stationery – by law, you must display your CRN on all official company stationery, including letterheads, invoices, websites, emails, and promotional materials.

A CRN is proof of your limited company’s incorporation, so it is required to prove that your company has been officially registered.

What happens if you lose your company registration number?

The most likely place to find your CRN is on your official certificate of incorporation, as well as in any official correspondence from Companies House. It is also available on the public register of companies.

VAT registration number: trading with VAT

In the UK, when a business’s VAT-taxable turnover exceeds £90,000, they must register for VAT. With this registration, they are given a VAT registration number.

VAT numbers vary across the UK. In England, Scotland, and Wales, it typically begins with the letters “GB,” followed by nine digits (so, GB123456789). However, in Northern Ireland, registered businesses that trade with the EU might begin with “XI” instead (so, XI123456789).

As a VAT-registered business, you need to display your VAT number on all invoices you raise. You will also need it to complete your VAT Return, pay your VAT bill, apply for a refund, and deal with certain suppliers.

What happens if you lose your VAT registration number?

HMRC will send your VAT registration number by post once you have successfully registered your business for VAT.

If you lose your number, you can find it in your:

• VAT registration certificate.
• Previous VAT Returns.
• Raised invoices.
• Accounting software.
• VAT notices from HMRC.
• Online VAT account.

You can also check a UK VAT number directly with HMRC.

Employer PAYE reference: for paying employees

Your Employer Pay As You Earn (PAYE) reference number is the final TIN mentioned. Employers use this TIN, which is also known as the “Employer Reference number” or “PAYE reference.”

Employers must register for PAYE as soon as their employees meet the following criteria:

• Being paid £96 or more per week,
• Getting expenses and company benefits,
• receiving a pension,
• having another job,
• Receiving Jobseeker’s Allowance, Employment and Support Allowance, or Incapacity Benefit.

HMRC sends over the employer PAYE reference number once registered, which is a code preceded by a 3-digit number and then followed by a forward slash and a tax office employer reference (e.g., 123/AB456).

Where can you find your employer’s PAYE reference number?

You can find your employer’s PAYE reference number:

• In HMRC correspondence.
• Payroll software.
• Previous PAYE filings.
• Payslips.
• P60s.
• By calling HMRC’s Employer Helpline on 0300 200 3200.

Employers must provide a PAYE reference when setting up their payroll, paying wages, issuing payslips, providing P60s, sending PAYE reports, and paying PAYE bills.

Know and understand your UK tax identifiers

While there is (officially) no such thing as a TIN in the UK, you should be aware of the five fundamental tax numbers in the UK and how they relate to different contexts.

Remember, different TINs apply to different business types, so it’s important to know what tax numbers you need as a sole trader compared to a limited company. Additionally, if you have a UK business and are trading with firms outside the UK, understanding the term TIN is helpful.

Whether you’re just starting out or looking to make sure your business is fully compliant, our team at 1st Formations is here to help. From setting up your company the right way to understanding TINs when you’re dealing with new markets, we provide expert guidance every step of the way.