What is a UTR (Unique Taxpayer Reference)?

Your UTR (Unique Taxpayer Reference) is a ten-digit code that enables HMRC to identify you as a taxpayer. If you’re registering as a sole trader, you’ll need to register for both Self Assessment and to pay National Insurance contributions.

After you register, if you haven’t already been given one before (eg because you’ve previously reported taxable self-employed or rental income), you’ll get your Unique Taxpayer Reference (UTR) by post within 15 working days (21 days if you live outside the UK). You’ll get your UTR sooner if you use the HMRC app to register.

You’ll need your UTR when completing your annual Self Assessment tax return, it won’t be accepted otherwise. If you’ve already registered for Self Assessment, your UTR will be quoted on various HMRC documents including your SA250 or your “welcome to Self Assessment” letter, previous Self Assessment tax returns, payment reminders, any notice to file a tax return lets you’ve received, your statement of account, HMRC app (if you use it) and your personal tax account on the GOV.UK/HMRC website. There’s no need to panic if you lose your UTR number, because you should soon be able to find it via all of the above. If you still can’t seem to find it, contact HMRC directly. It’s important to keep your UTR safe and private, to mitigate the risk of criminals using it to steal your identity. You’ll also need your UTR number for CIS (Construction Industry Scheme) tax-refund registration. If you’re a UK limited company director, you’ll receive your own UTR number so that you can complete your Self Assessment tax return. This will be different to your limited company’s UTR number.