UTR (Unique Taxpayer Reference)

A UTR (Unique Taxpayer Reference) is a 10-digit number issued by HM Revenue & Customs (HMRC).

It identifies you in the UK Self Assessment tax system.

Example format: 12345 67890

Who needs a UTR

You usually need a UTR if you must file a Self Assessment tax return in the UK.

This commonly includes people who:

  • Are self-employed
  • Receive UK rental income
  • Have foreign income that must be reported in the UK
  • Have capital gains to report
  • Are a company director (in some cases)
  • Have complex tax affairs not fully handled through PAYE

If all your UK tax is handled through employment (PAYE) and you have no additional income, you may not need one.

What a UTR is used for

Your UTR is used to:

  • File your annual Self Assessment tax return
  • Pay Income Tax or Capital Gains Tax owed through Self Assessment
  • Correspond with HMRC about your tax affairs

Without a UTR, you generally cannot submit a UK Self Assessment return.

UTR vs National Insurance number — not the same

People often mix these up:

NumberUsed for
UTRSelf Assessment tax returns
National Insurance numberSocial security contributions and employment records

You may have one, both, or neither, depending on your situation.

When non-UK residents might need a UTR

You may need a UTR even if you do not live in the UK, for example if you:

  • Own UK rental property
  • Receive other UK-source income that is not fully taxed at source
  • Need to report UK capital gains

In these cases, HMRC may require you to register for Self Assessment and obtain a UTR.

How to get a UTR

You get a UTR when you register for Self Assessment with HMRC.

The process usually involves:

  • Telling HMRC why you need to file a tax return
  • Providing personal details and contact information
  • Waiting for HMRC to issue your UTR by post

It can take a few weeks to receive your number, so it's important not to leave this until close to a filing deadline.

If you already have one

Your UTR stays the same for life (unless HMRC tells you otherwise).

You can find it on:

  • Previous Self Assessment tax returns
  • HMRC letters
  • Your HMRC online account

If you've lost it, you can recover it through your HMRC account or by contacting HMRC.

How Amanda uses this

Amanda may ask about your UTR when assessing:

  • Whether you are properly set up to file UK tax returns
  • Your compliance with UK reporting obligations (such as rental income)

It appears under Administrative Registrations & Status, because it reflects your registration with HMRC, not where you are physically present.