What is a UTR number?

For people registering for Self Assessment or looking for a lost UTR number.

Applies to: England, Scotland, Wales, Northern Ireland Last checked against official sources: 6 October 2026

A UTR (Unique Taxpayer Reference) is a 10-digit number HMRC gives you to identify your tax account.

You get one when you register for Self Assessment or set up a limited company.
It usually arrives by post about 15 days after you register, longer if you live abroad.
You can find it in your personal tax account, the HMRC app, or on past returns and HMRC letters.
On letters it may just be called "tax reference".
Register for Self Assessment by 5 October after the tax year ends, or you could get a penalty.

Key facts

10-digit HMRC number
Arrives in about 15 days
In personal tax account and app
Register by 5 October

What a UTR number is

A UTR is a Unique Taxpayer Reference. It is a 10-digit number that HM Revenue and Customs (HMRC) uses to identify your tax account. On HMRC letters it might just be called "tax reference".

You need it to deal with HMRC about Self Assessment, for example when you fill in a tax return.

Who gets one

You are	When you get a UTR
A person who must send a Self Assessment tax return (for example self-employed, a landlord or with untaxed income)	After you register for Self Assessment
A sole trader	After you register for Self Assessment as self-employed
A limited company	When the company is set up (a separate Corporation Tax UTR)
A partnership or trust	It has its own UTR, shown on its tax returns and HMRC letters

Your personal UTR and a company's UTR are different numbers. Do not mix them up.

How to get a UTR

Check if you need to send a tax return. GOV.UK has a checker for this.
Register for Self Assessment online. If you are self-employed, use the self-employed option.
Wait for your UTR. It usually comes by post about 15 days after you register. It takes longer if you live abroad.

Deadline: you must register by 5 October after the end of the tax year you need to report. For the 2025/26 tax year (ended 5 April 2026), that deadline was 5 October 2026. If you have not registered yet, do it now, as you could get a penalty. For income in 2026/27, the deadline is 5 October 2027.

If you registered before but did not send a return last year, you may need to reactivate your account instead of registering again. The online service tells you which to do.

Where to find your UTR

If you are a person or sole trader, look in:

your personal tax account online
the HMRC app
past tax returns
other HMRC letters, such as a notice to file a return or a payment reminder

For a partnership or trust, look on past tax returns and letters from HMRC.

For a limited company, you can ask for the Corporation Tax UTR online. HMRC posts it to the company's registered office address.

If you have lost your UTR

First check your personal tax account and the HMRC app. If you still cannot find it on any documents or online, contact HMRC.

Things to know

Your UTR is not the same as your National Insurance number.
If you are a company director, keep your personal UTR and the company's UTR separate.
The same rules apply in England, Scotland, Wales and Northern Ireland, because Self Assessment is run by HMRC for the whole UK.

Related guides

Where this comes from

Find a lost UTR number (GOV.UK)
Register for Self Assessment (GOV.UK)
Register for Self Assessment if you're self-employed (GOV.UK)

Get it done

This takes you to the official service, which is free to use.

Find your UTR number

Common questions

How long does it take to get a UTR number?

You usually get it by post around 15 days after you register. It takes longer if you live overseas.

What if I have lost my UTR number?

Check your personal tax account, the HMRC app or past HMRC letters. If you still cannot find it, contact HMRC.

Is a company UTR the same as my personal UTR?

No. A limited company gets its own Corporation Tax UTR, which you can ask for online.

Official sources

1.Find a lost UTR number (GOV.UK)www.gov.uk/find-utr-number
2.Register for Self Assessment (GOV.UK)www.gov.uk/register-for-self-assessment

Checked against GOV.UK on 6 October 2026

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