A Guide to Unique Tax Reference Numbers

Where can I find my UTR number? HMRC issues you with a UTR number when you register for a Self Assessment tax return. If you’ve already registered, your UTR can be found quoted on various documents…

5 Minute Read

Last Updated: 2nd December 2022

Where can I find my UTR number?

HMRC issues you with a UTR number when you register for a Self Assessment tax return.

If you’ve already registered, your UTR can be found quoted on various documents from HMRC including:

  • Your SA250, or your “welcome to Self Assessment” letter
  • Previous self-assessment tax returns
  • Reminders of payment
  • Your notice to file a tax return
  • Your statement of account
  • HMRC app

It can also be found on your personal account on the HMRC website.

What happens if I’ve lost my UTR number?

Don’t panic if you’ve lost your UTR number. Make sure to check all of the documents listed above to see if you can find it there. If you still can’t see it, you should contact HMRC directly by phone.

UTR numbers are unique to every individual so it’s important you keep yours safe. Losing a UTR number can be potentially dangerous as it can result in identity theft in a worst-case scenario.

Do you need a UTR number to submit your return?

Yes, you need a UTR number to complete your Self Assessment tax return successfully.

If you’re self-employed, or you own a limited company, you need a UTR number.

How do I get a UTR number?

One of the quickest ways to get a UTR number is by applying online and registering as self-employed. This can be done on HMRC’s website. As soon as you register for self-assessment or set up a limited company, you will automatically be issued a UTR number.

You can also call HMRC on 0300 200 3310 to ask about your UTR number. They may ask for some information (including personal details and your National Insurance number). They may end up directing you towards applying for your UTR number online.

Finally, you can write a letter to HMRC asking to send you a UTR number. Whilst this used to be the preferred option, people are gradually beginning to move towards online methods instead.

Writing a letter can involve a lot of back and forth (as well as mounting postage fees) as you trade information with HMRC, and the process can often take several weeks. If you’ve got tax to file quickly, then applying by letter may not be feasible.

What is a UTR number?

A UTR (unique taxpayer reference) number is a 10-digit number completely unique to each and every UK taxpayer. Whether the taxpayer is to register for self-employment or is an individual or part of a partnership or company, a UTR number is needed to file a Self Assessment tax return online or via post.

The most important reason why you need a UTR number is for completing self-assessment tax returns – but there are other reasons too.

UTR numbers are necessary for CIS (construction industry scheme) tax refund registration.

They are also important when working with accountants or other financial advisors.

Without a valid UTR number, your self-assessment tax return won’t be submitted correctly and this can result in a potential fine.

Furthermore, if you are self-employed and have not notified HMRC – and have therefore not received a UTR number – this too can be dangerous. If HMRC finds out, you may have to pay a hefty fine and potentially face criminal prosecution.

Registering for a UTR

You will automatically be registered for a UTR number when you first register for self-assessment tax returns on HMRC or launch a limited company.

You should notify HMRC online as soon as possible after becoming self-employed. Alternatively, you can fill in the form, print it and then post it to HMRC.

HMRC expect you to register for a UTR number within the first three months of opening a business.

After registering, you’ll be sent an activation code. This can take up to ten days to get to you.

Upon receiving your code, you need to register your online tax account using your activation code. You have a maximum of 28 days to this before your activation code expires.

What information do I need to register for a UTR number?

There are certain pieces of information you must know in order to register for a UTR number. This includes:

  • Basic information like your name, date of birth and address
  • Your national insurance number
  • A contact telephone number and email address
  • The date you started self-employment
  • Your business address and telephone number
  • Your business type

What is a UTR number for a company?

If you’ve set up a limited company, you’ll need a UTR number for the business. This is so that HMRC can identify which companies owe what in terms of tax.

Like a personal UTR, a company UTR is 10 digits long and will be issued to you when you register your limited company.

Be sure to keep this number on file, as you will need it for a variety of tax purposes in the future, including business taxes, tax returns, and corporation tax.

Again, a company UTR number can be found on relevant HMRC documents addressed to your company, such as the CT603, or your “notice to deliver a company tax return”.

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Blog content is for information purposes and over time may become outdated, although we do strive to keep it current. It's written to help you understand your Tax's and is not to be relied upon as professional accounting, tax and legal advice due to differences in everyone's circumstances. For additional help please contact our support team or HMRC.

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