Guide

UTR number: What it is, who needs one and how to get yours

UTR numbers are essential for tax compliance and business registration. Learn what they are and how to get yours.

A small business owner using Xero to monitor their finances on a laptop

Written by Jotika Teli—Certified Public Accountant with 24 years of experience. Read Jotika's full bio

Published Friday 14 November 2025

Table of contents

Key takeaways

• Register for Self Assessment online through HMRC's website to automatically receive your UTR number by post within 15 days, ensuring you meet the 5 October deadline following the tax year you need to file for.

• Locate your existing UTR number by logging into your HMRC personal tax account through Government Gateway, checking HMRC correspondence, or using the official HMRC mobile app where it appears at the top of your account summary.

• Protect your UTR number by only sharing it with HMRC, your accountant, or authorised tax advisors, and never provide it to cold callers, unsolicited emails, or anyone offering "tax refund services."

• Gather all required information before applying, including your full name, date of birth, National Insurance number, business start date, and business type to speed up your application and avoid delays.

What is a UTR number?

A UTR number is a 10-digit identifier that HMRC assigns to track your tax account and match payments to bills.

You get your UTR number automatically when you register for Self Assessment. You may have separate UTR numbers for your personal and business taxes.

You need your UTR number to:

Keep your UTR number safe, as you'll use it throughout your self-employment.

Who needs a UTR number?

You need a UTR number if you're:

  • Self-employed or a sole trader
  • A landlord with rental income
  • A limited company director
  • Part of a partnership or trust
  • A charity filing returns
  • Claiming CIS tax refunds in construction

Each business type requires Self Assessment filing, which means you need a UTR number. In one recent tax year, almost 300,000 people filed their return in the first week.

How to find an existing UTR number

If you've registered for Self Assessment, HMRC will have given you a UTR number.

Find your existing UTR number using these methods:

Government Gateway

Option 2: HMRC correspondence

  • Check tax return reminders or payment notices
  • Your UTR is printed on all HMRC letters

Option 3: HMRC mobile app

  • Open the official HMRC app
  • Navigate to your tax account summary

If these don't work:

Before you apply for a UTR number

Gather this information before applying:

Personal details:

  • Full name and date of birth
  • Home address
  • National Insurance number
  • Phone number and email address

Business information (if applicable):

  • Date you became self-employed
  • Business type (sole trader, partnership, limited company)
  • Business address
  • Business phone number

Gather these details before you apply to speed up your application and avoid delays.

How to apply for a UTR number for the first time

The fastest way to get a UTR number is registering for Self Assessment online through HMRC's website, but be mindful of the deadline for notifying HMRC, which is typically 5 October following the end of the tax year you need to file for.

Three application methods:

  • Online registration: Complete in one step, receive UTR by post in 15 days
  • Phone application: Call HMRC Self Assessment helpline
  • Written request: Send a letter to HMRC (slowest option)

Register online to provide all your information at once and receive your UTR and activation code automatically.

Differences in the UTR registration process

The exact process of getting a UTR number depends on your business structure. Here are the different registration processes you can pursue to get your UTR:

Sole trader

  • Register for Self Assessment tax returns.
  • You'll receive your UTR by post.

Register here for Self Assessment.

Partnerships

Register your partnership for filing returns. You'll then receive a UTR specific to the partnership.

Each partner must also register for Self Assessment. Each person then receives their own UTR number for their personal tax returns.

Register here for partnerships.

Companies

When you register your company with Companies House, you'll get a company UTR. Use this UTR when you file your corporation tax returns.

You file your personal taxes separately through Self Assessment, using your own UTR number.

Using your UTR number

Sharing your UTR number

Keep your UTR number secure. Treat it like sensitive financial information.

Safe to share with:

Never share with:

  • Cold callers claiming to be from HMRC
  • Unsolicited emails requesting tax information
  • Anyone offering "tax refund services"

Only share your UTR number with trusted sources to protect your tax information.

Simplify your tax compliance with Xero

A UTR number is just the start of your tax journey. Xero accounting software helps you keep accurate digital records, track your income and expenses, and prepare for your Self Assessment tax return with confidence.

Xero is recognised by HMRC and works in the cloud, so you can manage your finances from anywhere and stay compliant. Run your business, not your books.

## FAQs on UTR numbers

Here are answers to common questions about UTR numbers.

Can I submit a tax return online without a UTR number?

No, you cannot submit tax returns without a UTR number. HMRC requires this identifier to match your return and payments to your tax account.

Using the wrong UTR number can result in:

  • HMRC penalties for filing without due care, which can include interest charges or a 5% late-payment penalty if payments are not made on time
  • Delayed processing of your return
  • Payment allocation errors

Always double-check your UTR number before submitting returns to avoid complications.

What should I do if I've lost my UTR number?

If you've lost your UTR number, check your letters from HMRC. Your UTR number is printed on most HMRC correspondence and past tax returns.

If you have a Government Gateway account, sign in and navigate to the personal tax account section. Your UTR number is at the top of the page.

If you cannot find your UTR number, call HMRC's Self Assessment helpline.

How long does it take to get a UTR number?

You should receive your UTR number by post within 15 days after you register on HMRC's website. It may take longer if you live abroad.

Apply for your UTR number well before your next tax deadline. Some tax bodies have reported delays in processing registrations, so double-check your information to avoid issues.

If you need to contact HMRC, see what to expect.

How can I get my UTR number online?

  1. Register for HMRC's online service.
  2. Wait to receive your UTR number by post (this can take up to 15 days if you're in the UK, or 21 days if you're abroad).
  3. Once you've received your UTR number, sign up for Self Assessment.
  4. You'll be sent an activation code about a week later.
  5. Once you've received your code, use it to activate your account. You can access your Self Assessment account.

Disclaimer

Xero does not provide accounting, tax, business or legal advice. This guide has been provided for information purposes only. You should consult your own professional advisors for advice directly relating to your business or before taking action in relation to any of the content provided.

Start using Xero for free

Access Xero accounting software features for 30 days, then decide which plan best suits your business.

Disclaimer

Xero does not provide accounting, tax, business or legal advice. This guide has been provided for information purposes only. You should consult your own professional advisors for advice directly relating to your business or before taking action in relation to any of the content provided.

Start using Xero for free

Access Xero features for 30 days, then decide which plan best suits your business.