You're trying to file a tax return or set up an HMRC account, and you're stuck on one thing: your UTR. It's the 10-digit number HMRC uses to match your returns, payments and letters to the right tax record, and you can't do much without it.
The good news is that finding it is usually quick. If you've ever registered for Self Assessment or run a limited company, your UTR is almost certainly sitting in your Personal Tax Account, the HMRC app, or an old letter.
This guide walks you through every way to find it, how to recover a lost one, and the separate (online-only) process for a Corporation Tax UTR. It's written for sole traders, company directors and partnerships in the UK.
What is a UTR number?
A Unique Taxpayer Reference (UTR) is a 10-digit number HMRC gives you when you register for Self Assessment or when a company is set up for Corporation Tax. It looks like a plain string of digits, for example 1234567890, with no letters or spaces.
Think of it as your tax identity for returns and payments. HMRC uses it, alongside your name and other details, to make sure your records never get muddled up with someone else's.
It is not the same as your National Insurance number, and it is not the same as a company's registration number from Companies House. We'll come back to those differences below.
You'll need your UTR to file a Self Assessment return, pay the tax you owe, and use most of HMRC's online tax services.
How many UTRs might you have?
This trips a lot of people up, because you can genuinely have more than one.
If you're a sole trader, you get one personal UTR when you register for Self Assessment. It covers all your self-employed work, even if you run more than one trade under your own name. One person, one UTR.
If you run a limited company, the company gets its own UTR for filing the Company Tax Return and paying Corporation Tax. If you also draw a salary above the tax-free amount or take dividends and have to file Self Assessment, you'll have a separate personal UTR too. That's two numbers doing two different jobs.
If you're in a partnership, the partnership has its own UTR as an entity, and each partner has an individual UTR for their share of the profits on their own return.
It's worth labelling these clearly in your records so you never file with the wrong one. If you'd rather not juggle them at all, our Self Assessment service keeps the right reference on the right return.
How do you find your UTR in your Personal Tax Account?
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Your Personal Tax Account is the fastest place to find a personal UTR if you're registered for Self Assessment.
- Go to the Personal Tax Account sign-in page on GOV.UK.
- Sign in with your Government Gateway user ID and password. If you don't have one, you can create it on the same page.
- Find the Self Assessment section on your account.
- Your 10-digit UTR is shown there, usually near your tax account details.
If you've only just registered online, your UTR can appear here within a few days, sometimes sooner, so you often don't have to wait for the postal letter.
Can you find your UTR on the HMRC app?
Yes. The official HMRC app shows your UTR once you've signed in, and it's handy if you're away from your desk.
Download the app from the Apple App Store or Google Play, then sign in with the same Government Gateway details you'd use online. Open the Self Assessment section and your UTR is displayed there.
The app also shows payment deadlines and what you owe, so it's a useful one to keep on your phone. Just keep the device secure, as your UTR is sensitive tax information.
Which documents show your UTR?
If you're not set up online yet, your UTR appears on several HMRC documents. Look for it on:
- The "Welcome to Self Assessment" letter HMRC sends when you first register
- Your Self Assessment tax return and any notices to file
- Self Assessment statements and payment reminders
- Company Tax Return notices for limited companies
- Previous letters from HMRC about your tax affairs
It's usually labelled "UTR" or "Tax Reference", often near the top of the page. If you've recently moved, your accountant or business partner may also hold copies of correspondence that shows it.
How do you get a UTR if you don't have one yet?
If you've never had a UTR, applying is free and done directly with HMRC. Never pay a third party for something HMRC provides at no cost.
Sole traders and individuals: register for Self Assessment on the GOV.UK registration page. You'll need your National Insurance number and some basic personal details. You'll usually get your UTR by post around 15 days after you register, and longer if you're overseas. If you register online and set up your Personal Tax Account or the app, it often shows up sooner.
Watch the registration deadline: if you need to send a return for a tax year, you must register by 5 October following the end of that tax year. So for income earned in the 2025/26 tax year, register by 5 October 2026.
Limited companies: when you incorporate through Companies House, HMRC is notified automatically and posts the company UTR to your registered office, usually within a few weeks. You don't apply separately.
Partnerships: the nominated partner registers the partnership for Self Assessment. HMRC then issues a UTR for the partnership, and each partner registers for their own.
Applying more than once won't speed things up, and duplicate applications can slow you down, so apply once.
If you've just started out and want this handled cleanly from day one, talk to our team for sole traders or limited companies.
How do you find a lost personal UTR?
Misplacing a UTR is common, and you have several ways to get it back:
- Personal Tax Account. The quickest route. Sign in and check the Self Assessment section.
- HMRC app. Sign in and open the Self Assessment section.
- Old paperwork. Any past return or HMRC letter should show it.
- Your accountant. If you use one, they'll have it on file.
- Phone HMRC. If none of the above works, contact HMRC's Self Assessment helpline. Have your National Insurance number and personal details ready so they can verify who you are.
How do you request a lost Corporation Tax UTR?
A company UTR works differently. For security, HMRC won't read out a Corporation Tax UTR over the phone, so you request a copy online instead.
- Use HMRC's request your Corporation Tax UTR online service.
- You'll need your Company Registration Number (the number from Companies House) and the registered company details.
- Submit the request.
- HMRC posts the UTR to your company's registered office address.
A quick but important point: your company UTR is not your Company Registration Number (CRN). The CRN comes from Companies House when you incorporate; the UTR comes from HMRC for tax. Limited companies have both.
Before you request the letter, make sure your registered office address at Companies House is current, otherwise it may not reach you. If you'd like us to keep your filings and references in order, see our Corporation Tax service.
Ready to hand the tax admin to someone else?
Chasing references, deadlines and forms eats into time you'd rather spend running your business. Zmartly handles your Self Assessment and Corporation Tax filings end to end, so you always know the right number is on the right return.
Book a free 20-minute call with a Zmartly accountant and we'll take it from here.
FAQs about UTR numbers
What does a UTR number look like?
A UTR is always a 10-digit number with no letters or spaces, such as 1234567890. It's issued automatically when you register for Self Assessment or when a company is set up for Corporation Tax.
How long does it take to get a UTR after applying?
You'll usually get your UTR by post around 15 days after you register for Self Assessment, and longer if you're overseas. If you register online, it often appears in your Personal Tax Account or the HMRC app within a few days.
Is my UTR the same as my National Insurance number?
No. Your National Insurance number identifies you for employment and benefits, while your UTR is used for tax returns and business tax. They're different numbers issued for different reasons.
Can I have more than one UTR?
Yes. If you run a limited company and also file your own Self Assessment, you'll have one UTR for the company and one for yourself. Partnerships have a separate UTR for the partnership and one for each partner.
Do I need a UTR if I'm only employed?
Usually not. If you're in standard PAYE employment with no other income that needs reporting, your employer handles your tax through payroll and you won't need a UTR. You only need one if you have to file Self Assessment.
Can HMRC give me my company's UTR over the phone?
No. For security, HMRC won't provide a Corporation Tax UTR by phone. You request a copy online and HMRC posts it to your registered office address.
What's the difference between a UTR and a Company Registration Number?
Your Company Registration Number (CRN) is issued by Companies House when you incorporate. Your UTR is a separate number issued by HMRC for tax. Limited companies have both.
