Does Your UTR (Unique Taxpayer Reference) Number Change?

A unique taxpayer reference (UTR) number is given out to businesses that register for self-assessment tax returns or organisations that register as a limited company. This ten-digit code is needed and used by both the organisation in question and by HMRC, as it’s an essential element in preventing errors. Typically, your UTR will not change, at least not outside of very specific circumstances.

But what are these circumstances? In this article, Real Business outlines the answer to this question, as well as what happens when you use the wrong UTR number, how to find it, and more.

What are the circumstances in which your UTR number changes?

When you get a UTR number, HMRC intends for you to keep it permanently. It’s designed this way to keep things stable and streamlined despite any event that could otherwise confuse these matters, such as relocating. If you could change your unique taxpayer reference number at will, that could cause confusion with your tax account matters.

However, as previously stated, there are instances in which your UTR number can change. Such as:

• Identity theft – It is not unheard of for unscrupulous individuals to file false self-assessment tax returns or claim refunds with another’s unique taxpayer reference number. In the event of this happening, HMRC will cancel the compromised number and issue a new one to you. All official records, such as your previous tax returns, will be retained and transferred over.
• Duplicate UTR numbers – If a new business or limited company is given a unique taxpayer reference number that is the same as another organisation’s without realising, they will consolidate records and cancel one UTR number, providing another in its stead.
• Change in legal business structure – This is a technicality. If you were to change your business model from a sole trader to a limited company, the separate legal entity would gain a new, unique taxpayer reference number. This means that you’d be using a different UTR for the company tax return, and your “own business” UTR for separate dealings.
• Serious HMRC administrative error – Possibly the rarest case in this list, but if HMRC makes a foundational error regarding how your UTR number is issued (such as being linked to the wrong national insurance number).
• Closure of a tax account by HMRC – If a taxpayer is rendered unable to generate tax bills for any reason, such as being declared dead or incarcerated, HMRC may deactivate the UTR number.
• Mergers or acquisitions – If a limited company merges, or is absorbed into, another company, then its UTR number may be closed, and all tax responsibilities transferred to a different one.

When is a UTR number used?

Your unique taxpayer reference number is a mandatory part of the following actions:

• Filing a tax return – Individuals must use their personal UTR number on their self-assessment return (SA100), and companies must use their UTR to file a company tax return.
• Paying your tax bill – HMRC requires you to use your UTR number as a payment reference when you pay via bank transfer, online transfer or a cheque. The correct format can be found on your tax statement.
• Receiving payment reminders and notices – HMRC uses UTR to send notices to file returns, tax calculations, payment reminders and late payment penalty letters.
• HMRC communication – Whether you’re contacting HMRC via HMRC’s self-assessment helpline, the HMRC app or via post, you will need a UTR number to confirm your identity. Failure to give it over can lead to delayed access by confirming via an alternate security method.
• Using a personal tax account or HMRC app – When logging into your tax account, your UTR is required for reviewing previous tax returns, current tax bill and payment history.
• Working with an accountant or tax agent – Your accountant or tax advisor will require your UTR number to do your tax duties. They will be barred without it.
• Claiming tax reliefs, rebates or refunds – Claiming for the following will require a UTR number:
  • Work-related expenses
  • Pension contributions
  • Charitable donations
  • Business mileage
• Proving income – UTR numbers are often required when you must prove income for larger-scale investments/purchases, such as mortgages, loans, visas, etc.
• Past or ongoing investigations, appeals or corrections – If HMRC opens an enquiry or challenges a tax decision, your UTR number will be the main form of correspondence tracing.

What happens if you use the wrong UTR number?

Making a mistake and using the wrong UTR number can completely disrupt HMRC’s functions, resulting in delays or financial penalties. In detail:

• HMRC can’t match your self-assessment tax return or payment – HMRC may be unable to link your self-assessment to your account, risking being labelled under a “non-filing” or “non-payment” status. This, of course, leads to penalties due to the failure of the return or payment reminders.
• Delays in processing – Even if HMRC can link your UTR number to your account, the discrepancy may be enough to place it in a queue for manual review. This delay could set you over the deadline.
• Data may be applied to the wrong account – If the incorrect UTR number you input belongs to another account, then your tax return may end up credited to them. This can lead to double reporting for them and missing records for you.
• Risk of checks/investigations – Consistent mismatches and errors involving the wrong UTR could trigger an investigation, as HMRC could consider it indicative of fraud or negligence.
• Accountant or agent errors – If your trusted agents or accountants use the wrong UTR number, you will still be held legally responsible.

If you realise you’ve used the wrong UTR number, contact HMRC immediately to rectify the issue. Alongside the correct number, ensure you have your national insurance number, proof of income (or other documents), and copies of the original return/payment.

Where do I find my UTR number?

Your UTR number can be found in several official places:

1. HMRC app – The easiest, surefire way to get access to your UTR number is through the official app.
2. HMRC welcome letter – When you first register for self-assessment tax returns or a limited company, you will get a UTR number in the post.
3. Self-assessment notices and reminders – HMRC references your number in an official use capacity.
4. Online tax account – Your online tax account on Gov.uk will display your UTR number in the “self-assessment” category.
5. Previous self-assessment tax returns – Also known as SA100 forms, your UTR will be listed on these documents.

What happens if I don’t keep my UTR number safe?

There are several concerning statistics revolving around fraud using UTR numbers. Fraudsters impersonate taxpayers to gain access to HMRC systems using minimal identifying information. With that, they can:

• Create fake self-assessment accounts
• Submit false tax returns
• Claim illegitimate tax returns
• Divert payments to their bank accounts

The stats on scam statistics involving UTR numbers are as follows:

• Self-assessment rebate scams – In the 12 months to January 2024, 207,800 suspicious contacts were reported to HMRC and 79,000 (38%) involved self-assessment rebate scams, which worked by redirecting refunds by changing bank details in the account.
• Scam referrals – Between 2023 and 2024, over 144,298 scam referrals were recorded, half of which targeted self-assessment users.
• Government gateway breach – NI and UTR numbers were stolen during a government gateway breach and were used to file false self-assessment tax returns. Although many were blocked, around £47 million in total was stolen. Accounts were locked.
• Prevented scams – HMRC blocked around £1.9 billion in fraudulent claims in the same year.

How do I keep my UTR number safe?

The following are some effective measures to keep your UTR number safe:

1. Never share your UTR number publicly – Do not post your UTR number online, or include it within public documents.
2. Share only with associated professionals – HMRC, authorised tax agents, and, of course, your accountant.
3. Watch for phishing attempts – HMRC never asks for UTRs via unsolicited emails or texts. Always check the email address of any email asking for personal information for confirmation, and only ever communicate such over secure channels.
4. Keep tax documents locked or encrypted – Many files have protection measures, such as Adobe Acrobat, Microsoft Word and more.
5. Report suspected misuse – If you receive correspondence that hints that your UTR has been used fraudulently, report it immediately.
6. Use secure channels when submitting your UTR number – Only use it on official HMRC platforms or secure accounting software.

Conclusion

Overall, your UTR number will likely never change unless there’s an error. This is for consistency and reliability. In the event the UTR number changes, HMRC will send you an official letter with the new number and the reason it was changed.

FAQ – Can a UTR number change before self assessment tax return deadline triggers late penalties?

Yes, it will. HMRC has a no-tolerance rule when it comes to deadlines that encompass all late filings. However, they also have an appeals system. If the UTR number change is close to the deadline, and the late filing was not too far over the line, chances are that they’ll waive the late registration fee. That being said, you will need to ensure you have the correct information on hand.

FAQ – Can I request to get a UTR number changed?

No, you cannot request to have HMRC change your UTR number. That would pose too many risks for HMRC, such as data fragmentation, opening the possibility of fraud, or creating duplicate records. UTR numbers are intrinsically designed to be permanent, and it remains up to HMRC to make the changes.

FAQ – Do I need to register for self-assessment again if my unique taxpayer reference number changes?

No. HMRC simply transfers all of your data when you get a UTR number changed. There is no need to register for self-assessment again.

Instead, focus on updating your records with your new UTR number. Tell your accountant or your tax agent that they’ll need to update their authorisation with the new code, and make a final check on your HMRC account that the number has been successfully changed. You can always contact HMRC’s self-assessment helpline if you’re unsure.

FAQ – What happens if I stop being self-employed?

The only thing you need to do if you’ve stopped trading as a self-employed individual is to contact HMRC. Use your personal account or contact the helpline to stop all future self-assessment notices and possible late filing penalties.

Your UTR number will remain active, it stays on record until you are deceased. If you return to being self-employed, all you need to do is return to using the code.