What is a UTR number?

A UTR number is your ‘unique taxpayer reference’ number. HMRC assigns each self-assessment taxpayer a different number in order to track their tax records.

All UTR numbers have 10 digits, and sometimes there’s a letter ‘K’ at the end.


Who needs a UTR number from HMRC?

You only need a UTR number if you submit a self-assessment tax return.

This could be the case if you’re self-employed or have set up a limited company, if you owe tax on savings interest, dividends or capital gains, or if you earn more than £100,000.

There are a range of other circumstances where you’ll be required to submit a tax return.


How to get a UTR number

You won’t automatically be given a UTR number. You need to register for self-assessment to be issued with one. Here’s how to do it:

  • Register for self-assessment online: Before you submit a tax return for the first time – say, after you’ve started a new business – you need to register for self-assessment, which you can do on the HMRC website. When you do this, you will automatically be assigned a UTR number, which will be sent in a letter through the post.
  • Apply over the phone: you can call HMRC on 0300 200 3310 to ask about your UTR number. You may have to provide some details, and they may still direct you to apply online.
  • Apply by post: you can write to HMRC to request a UTR number. Be aware that it’s likely to take a long time as several letters are likely to go back and forth asking you to provide information.

How long does it take to get a UTR number?

After registering for self-assessment you should receive your UTR number in 10 working days or 21 working days if you’re abroad.


Information you’ll need to get your UTR number

To register for self-assessment, you’ll need the following information:

  • Full name
  • Current address
  • National Insurance number
  • Date of birth
  • Phone number
  • Email address

If you run your own business, you may also need:

  • The date you started being self-employed
  • Type of business
  • Business address
  • Business phone number

I’ve lost my UTR number: what should I do?

If you have already been issued a UTR number but can’t find it, call HMRC’s self-assessment helpline (0300 200 3310).

To help them find your UTR number, you should have your National Insurance number to hand.

Submitting a tax return without your UTR number could result in a fine, as HMRC may not be able to match your return to their records before the submission deadline.