If you're self-employed, run a limited company, or file a Self Assessment tax return, HMRC will have given you a Unique Taxpayer Reference — usually shortened to UTR. It's a 10-digit number that identifies you (or your company) for tax purposes, and you'll need it for almost any conversation with HMRC.
The trouble is, most people only need their UTR once a year, and by the time they go looking for it, the letter HMRC sent has long since vanished into a drawer. Here's where to look.
What a UTR actually looks like
A UTR is always 10 digits. You may sometimes see it written with a 'K' on the end (e.g. 1234567890K) — that's a check character HMRC uses internally and you can usually ignore it.
Sole traders and individuals get a personal UTR. Limited companies get a separate company UTR — they are not the same number, so check which one you actually need before you start hunting.
Where to find your personal UTR
- Your HMRC Self Assessment 'Welcome to Self Assessment' letter (SA250), sent when you first registered.
- Any previous Self Assessment tax return you've filed.
- Notices to file a tax return, statements of account, or payment reminders from HMRC.
- Your HMRC online account: sign in to the Personal Tax Account at gov.uk, go to Self Assessment, and your UTR appears at the top of the page.
- The HMRC app — same login as your online account.
Where to find your company UTR
HMRC posts your company UTR to your registered office address within about 14 days of the company being formed at Companies House. It comes on a letter titled 'Information for new companies' (form CT41G).
- The original CT41G letter from HMRC.
- Any Notice to deliver a Company Tax Return (form CT603).
- Previous Corporation Tax payment reminders or statements.
- Inside HMRC's online Corporation Tax service if you've enrolled for it.
Lost it completely? Here's what to do
If you genuinely cannot find your UTR anywhere, you can ask HMRC to post it to you again. For your personal UTR, sign in to your Personal Tax Account on gov.uk and request it under Self Assessment, or call HMRC's Self Assessment helpline. For a company UTR, use the 'request your company UTR' service on gov.uk — you'll need the company name and registration number.
HMRC will only post the UTR to the address they hold on file, and it usually arrives within 10 to 15 working days. They will never email or text it to you, so be cautious of any message claiming otherwise.
When you'll actually need it
- Filing your Self Assessment tax return.
- Paying tax to HMRC (it goes in the payment reference).
- Registering for VAT, PAYE or the Construction Industry Scheme.
- Authorising an accountant to deal with HMRC on your behalf.
- Applying for certain mortgages or loans where the lender wants proof of self-employed income.
Need a hand?
If you're new to Self Assessment, setting up a limited company, or just tired of the HMRC paperwork, we deal with this every day for businesses across Yorkshire and beyond. Get in touch and we'll take it off your plate.
Frequently asked questions
- Is my UTR the same as my National Insurance number?
- No. Your National Insurance number is 9 characters (letters and numbers) and is used for benefits and state pension. Your UTR is 10 digits and is used only for tax.
- Do I need a UTR if I'm employed (PAYE only)?
- No. UTRs are only issued when you register for Self Assessment, set up a limited company, or HMRC asks you to file a tax return.
- How long does it take to get a new UTR?
- If you're registering for Self Assessment for the first time, HMRC normally posts your UTR within 10 working days (21 days if you live abroad). For a replacement, expect 10 to 15 working days.
Need help with your tax affairs?
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