What is a UTR number and how do I get one?

A UTR (Unique Taxpayer Reference) is a 10-digit number that HMRC uses to identify your tax record. You need it to file a Self Assessment return, set up a Business Tax Account, or communicate with HMRC about your taxes. How to get one: 1. Register for Self Assessment at gov.uk/register-for-self-assessment 2. HMRC sends your UTR by post within 10 working days (up to 21 days if abroad) 3. You can also call HMRC on 0300 200 3310 if you're already registered but lost your UTR You need to register by 5 October after the end of the tax year in which you became self-employed. For example, if you started a business in 2024/25, register by 5 October 2025. Your UTR appears on: HMRC letters and notices, your online Personal Tax Account, previous Self Assessment returns, and letters from your accountant.

  • UTR = 10-digit number assigned when you register for Self Assessment
  • Register online at gov.uk/register-for-self-assessment
  • Allow 10–21 working days to receive UTR by post
  • Register by 5 October after the tax year you started self-employment
  • Find your existing UTR in HMRC letters, Personal Tax Account, or previous returns

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