How to find your UTR number — and why you might already have one

What is a UTR?

A UTR (Unique Taxpayer Reference) is a 10-digit number HMRC uses to identify you for tax purposes. It is sometimes labelled "tax reference" on HMRC correspondence.

Every person registered for Self Assessment has one. HMRC issues it once and it never changes — even if you stop filing returns for years, your UTR stays on HMRC's system.

Do you already have one?

This is the question to answer before anything else. You might have a UTR and not realise it.

You likely already have a UTR if any of the following apply:

• You have ever submitted a Self Assessment tax return
• You have previously been self-employed or done any freelance work
• You have been a company director and received a notice to file from HMRC
• You have declared rental income to HMRC
• You have received any HMRC letter with a 10-digit reference number on it

Where to find your UTR

If you think you might have one, here is where to look.

1. 1
   Any HMRC letter

   Your UTR appears on most correspondence from HMRC — notices to file, payment reminders, Self Assessment statements. It is usually in the top right corner. The SA250 "Welcome to Self Assessment" letter is the most common place people find it for the first time.

2. 2
   The HMRC app

   Download the HMRC app (available on iOS and Android), log in with your Government Gateway details, and your UTR is displayed at the top of the Self Assessment section.

3. 3
   Your personal tax account

   Log into your HMRC personal tax account at gov.uk using your Government Gateway user ID and password. Navigate to Self Assessment and your UTR will be shown in your account details.

4. 4
   Previous tax returns

   If you have ever had an accountant prepare a return for you, the UTR will appear on the return itself and on any tax computations or HMRC correspondence they sent you.

5. 5
   Your accounting software

   If a previous accountant set you up on software such as QuickBooks or Xero, your UTR may already be saved there.

What if you cannot find it?

If you have searched and cannot locate it, the next step depends on whether you are certain you have never been on Self Assessment.

If you are not sure

Call HMRC's Self Assessment helpline on 0300 200 3310. Have your National Insurance number ready. HMRC can confirm over the phone whether a UTR exists against your record.

If you cannot find it but know it exists

HMRC will reissue your UTR by post after verifying your identity. This typically takes 10 to 15 days. You can request this through your personal tax account, by phone, or by post to: HMRC Self Assessment, BX9 1AS.

What if you definitely do not have one?

If you have never been on Self Assessment and none of the above apply, then you do not have a UTR yet. Registering as self-employed is what triggers HMRC to issue one.

As your accountant, we can handle that registration on your behalf. Once HMRC issues your UTR — usually within 10 working days of registration — we can set up the formal authorisation that allows us to deal with HMRC for you.

A note on timing

HMRC issues UTRs by post. If you are starting a new business and need an accountant in place before your first filing deadline, the earlier you start this process the better. The authorisation stage involves additional letters, and each one takes time.