How to Get a UTR Number: Find, Request or Replace Yours

Quick answer: To get a UTR number, register for Self Assessment with HMRC, for example as a sole trader. HMRC then posts your 10-digit Unique Taxpayer Reference, usually about 15 days after you register. If you already have one, find it in your HMRC online account, the HMRC app, old tax returns or HMRC letters.

Your Unique Taxpayer Reference, or UTR, is the number HMRC uses to match you to your Self Assessment record. You cannot file a return without it, construction contractors need it to pay you at the lower CIS rate, and some clients ask for it before they set you up as a supplier. This guide explains how to get a UTR number for the first time, how long it takes in 2026, where to find a lost one and how it relates to the details on your invoices.

Important: This is general information about UK tax administration as of 2026, not tax advice. Check GOV.UK or speak to a qualified adviser about your own situation.

What a UTR number is

A UTR is a 10-digit reference that HMRC issues when you register for Self Assessment or when a limited company is set up. GOV.UK notes it may also be called a tax reference. It identifies one taxpayer record, so it appears on your tax returns, statements, payment reminders and letters about penalties or repayments.

There are two main kinds:

• Personal (Self Assessment) UTR: for sole traders, partners, landlords, company directors who file a return and anyone else with income that needs reporting.
• Corporation Tax UTR: for a limited company. It belongs to the company, not to you as a director.

Partnerships also get a partnership UTR, and each partner keeps their own personal UTR as well. If you are weighing up the two business structures, our comparison of sole trader vs limited company explains how the tax records differ.

How to get a UTR number for the first time

You do not apply for a UTR on its own. It is issued as part of registering for Self Assessment. Here is the process for a new sole trader:

1. Check you need to register. GOV.UK says you must register as a sole trader if you earn more than £1,000 from self-employment in a tax year (6 April to 5 April). Other reasons include untaxed rental income, large savings or investment income, or being a partner.
2. Have your National Insurance number ready. GOV.UK says you need one to register. You will also give your name, address, date of birth, contact details, the date you started trading and a description of the business.
3. Use the online registration service. Start from the GOV.UK page for registering as a sole trader. You sign in or create sign-in details, and the service sets up both your Self Assessment record and Class 2 and Class 4 National Insurance as self-employed.
4. Wait for the letter. HMRC posts your UTR, usually about 15 days after registration (longer if you live abroad). The number also appears in your online account once it is set up.
5. Activate any codes you are sent. Some letters include an activation code for online services. Use it within the time stated or you may need to request a new one.

Our step-by-step guide on how to register as self-employed in the UK walks through the registration screens in more detail.

The deadline that matters

You must tell HMRC by 5 October after the end of the tax year in which you need to file. For income in the 2025 to 2026 tax year, the deadline was 5 October 2026. For income you start earning in the 2026 to 2027 tax year, it is 5 October 2027. GOV.UK warns that if you tell HMRC after the deadline you could get a penalty. The official guidance on registering for Self Assessment if you are self-employed has the current dates.

How long it takes to get your UTR

The standard timescale on GOV.UK is about 15 days by post. That sounds short, but delays happen when your address details do not match HMRC records, when you register close to a deadline, or when you live overseas.

Situation	Typical timing as of 2026	What to do
Registered online, UK address	About 15 days by post	Watch for the letter and check your online account
Living outside the UK	Longer than 15 days	Register early and keep your address up to date
Registered close to 5 October or 31 January	Can be slower in peak periods	Register as soon as trading starts
Limited company (Corporation Tax UTR)	Sent after incorporation to the registered office	Request it online if it does not arrive

Worked example: registering in time

Aisha starts freelancing as a copywriter on 1 June 2026 and invoices £2,400 in her first month, so she is well over the £1,000 trading allowance. Her first tax year of trading is 2026 to 2027, so she has until 5 October 2027 to register. She registers on 1 July 2026 anyway. At about 15 days, her UTR arrives around 16 July 2026, leaving her more than 18 months before her first online return is due on 31 January 2028. If she had waited until 4 October 2027, a 15-day wait would have pushed her UTR to around 19 October 2027, after the registration deadline.

Where to find your UTR number

If you have registered before, you probably already have a UTR, even if you have not filed for a few years. A UTR does not change. GOV.UK lists these places to look:

• Your HMRC online account (Personal Tax Account), under Self Assessment.
• The HMRC app, after you sign in.
• Previous tax returns, usually on the first page.
• HMRC letters, such as notices to file a return and payment reminders.
• Your Self Assessment statement, if you have one.

For a limited company, check previous Corporation Tax returns and HMRC letters, or request the company UTR online. HMRC sends it to the address Companies House holds for the company. The official page on finding a lost UTR number lists each route.

What to do if you have lost your UTR

If none of the places above work, contact HMRC through the Self Assessment contact options on GOV.UK. Have your National Insurance number, address and date of birth ready. HMRC will normally post the UTR to the address on your record rather than give it out over the phone, so make sure that address is current.

Avoid paying a third-party website to "find" your UTR. Only HMRC can issue or confirm it, and handing your National Insurance number to an unknown service creates a fraud risk.

If you registered years ago and stopped filing

You keep the same UTR. If you did not need to file last year but need to again, the registration service lets you reactivate your record rather than creating a new one. Registering twice can create duplicate records and delay your return.

UTR vs other UK tax numbers

Small business owners often juggle several HMRC references. This table shows which is which:

Number	Format	Who has it	Used for
UTR	10 digits	Self Assessment taxpayers, companies, partnerships	Tax returns, CIS verification, HMRC correspondence
National Insurance number	2 letters, 6 digits, 1 letter	Every UK worker	NI record, registering for Self Assessment
VAT registration number	GB plus 9 digits	VAT-registered businesses	Must be shown on VAT invoices
Company registration number	8 characters	Limited companies	Companies House records, company documents

The VAT number is the one with strict invoice rules. Our VAT invoice guide covers what a VAT-registered business must show, and the threshold for registering is explained in our post on the UK VAT registration threshold.

Do you need your UTR on invoices?

For most sole traders, no. UK law does not require a UTR on an ordinary invoice. What a sole trader should show is their name, any business name, an address for service, the customer's details, a unique invoice number, dates, a description of the work and the amount due. Our guide to the sole trader invoice in the UK sets out the full list, and you can build one in minutes with the UK invoice generator.

Many people leave the UTR off deliberately, because it is a personal identifier that fraudsters can misuse. Give it to a client only when there is a clear reason, such as supplier onboarding with a known business or CIS.

The CIS exception

In construction, contractors must verify subcontractors with HMRC before paying them, and they need your UTR to do it. If HMRC cannot match you, the contractor deducts 30% instead of 20%. On a £1,500 labour payment that is £450 withheld instead of £300, a £150 difference you would have to wait to reclaim through your return. Our CIS invoice template guide explains exactly what to show.

What you do with your UTR next

Once you have your UTR, you will use it every year. The main jobs:

• File your return. The online deadline for the 2025 to 2026 tax year is 31 January 2027. Our guide to the Self Assessment tax return covers each box.
• Pay your tax. Your UTR followed by the letter K is the payment reference for Self Assessment payments. If your bill is £1,000 or more you may also need to make payments on account.
• Sign up for Making Tax Digital if it applies. Since 6 April 2026, sole traders and landlords with qualifying income over £50,000 must keep digital records and send quarterly updates. The threshold falls to £30,000 from April 2027. See our Making Tax Digital for Income Tax guide.
• Keep good records. Number every invoice consistently with the invoice number generator and log costs so you can claim allowable expenses.

UTRs for partners, directors and landlords

Not everyone who needs a UTR is a sole trader. The route is slightly different depending on how you earn your money:

• Partners: the partnership is registered by its nominated partner and gets its own UTR for the partnership return. Each partner also needs a personal UTR for their own Self Assessment return, so a two-person partnership involves three UTRs in total.
• Company directors: the company receives a Corporation Tax UTR after incorporation. A director only needs a personal UTR if they have to file Self Assessment, for example because they receive dividends above the allowance or have other untaxed income. Our guide to UK dividend tax rates explains when dividends create a return.
• Landlords: you register for Self Assessment because of property income rather than as self-employed, and the UTR works in exactly the same way.

Whichever applies, keep each number in a clearly labelled place and give your accountant both if you have a personal and a company UTR.

Common UTR mistakes to avoid

• Waiting until you need to file. Registration has its own 5 October deadline, months before the return deadline.
• Registering twice. If you have ever filed, you already have a UTR. Reactivate rather than starting fresh.
• Using the company UTR on a personal return (or the other way round). Directors often have both.
• Sharing your UTR widely. Keep it for HMRC, your accountant and contractors who need to verify you.
• Letting your address go out of date. UTR letters, activation codes and reminders go by post.

Get set up and start invoicing

Getting a UTR number is simple once you know it comes from registering for Self Assessment: register as soon as you start trading, allow about 15 days for the letter, and keep the number somewhere safe alongside your National Insurance number. While you wait, you can already trade and invoice. Create a professional, numbered invoice for free with our invoice generator, or pick a clean layout from our minimal invoice template. Download the result as a PDF invoice you can email, print or upload to a client portal.