FAQ 026 | Why Do Duplicate UTRs Happen, and How Should They BeDealt With?

Author: SJW Research & Intelligence

Brand: SJW UK Properties

Why do duplicate UTRs happen?

This is a case we have genuinely encountered in acting for overseas landlords at SJW UK Properties since 2015. It is uncommon, but where it does occur and is not dealt with promptly, it can generate penalties and interest on an ongoing basis. We hope this article helps overseas landlords understand why it happens and how to put it right.

What is a UTR (Unique Taxpayer Reference)?

A UTR, or Unique Taxpayer Reference, is the number that identifies an individual taxpayer. As the name suggests, in principle a taxpayer should hold only one UTR for life. However many properties you go on to own, and whether or not you change managing agent or accountant, you should normally continue to use the same UTR for Self Assessment.

Why do duplicate UTRs arise?

Based on our practical experience since 2015, this is rare but it does happen. One cause is as follows. Where a landlord already holds a UTR but, on applying for the NRL again or dealing with other tax formalities, does not tell HMRC that they already have one, or leaves the existing UTR off the form, HMRC may in some circumstances create a fresh tax record and issue a new UTR. The same landlord then holds two UTRs.

It is worth repeating that the full name of a UTR is Unique Taxpayer Reference, and that in principle each taxpayer should hold only one for life. Holding two is not a normal state of affairs and should be raised with HMRC as soon as possible.

What happens if one person holds two UTRs?

This is the most important part of the whole issue. UK Self Assessment operates by individual. However many properties or sources of income a person has, all of them should be brought together in a single Self Assessment return filed under one UTR. Where a taxpayer holds two UTRs but files an annual return under only one of them, the other UTR may still appear in HMRC’s system as requiring a Self Assessment return. If this is not addressed, it can continue to generate late filing penalties, late payment interest and reminders from HMRC.

Why do duplicate UTRs keep generating penalties?

Clients often ask: “I have filed my return. Why is HMRC still fining me?” The reason is that where a taxpayer holds two UTRs and HMRC has not been told to close or deactivate one of them, HMRC’s system may continue to treat that UTR as requiring a Self Assessment return for every tax year. If no return is ever filed against it, penalties and interest may continue to accrue. Filing under one UTR is therefore not enough on its own. What matters is contacting HMRC promptly, having the tax records checked, and closing the duplicate UTR.

What should you do if you have a duplicate UTR?

There is no need for undue concern. In our experience the situation can normally be resolved. The key is to contact HMRC as soon as possible and explain that the same taxpayer holds two UTRs. Once HMRC has verified the position, it will usually help to:

 confirm which UTR is to remain in use;

 deactivate or close the duplicate UTR;

 update the associated tax records.

Once this has been done, the duplicate UTR does not normally continue to generate penalties or

interest.

Two real cases from SJW

Case one: HMRC issued a duplicate UTR. An overseas landlord had been completing his own Self Assessment for some time. SJW UK Properties then began providing lettings management for his UK property and assisting with the related tax formalities. During that process we found that HMRC had sent the client a further UTR notice. The landlord ended up holding two different UTRs. After a professional adviser had contacted HMRC, it was confirmed that a duplicate tax record had been created, and the matter was resolved.

Case two: the client did not mention a second property and an existing tax record. Another overseas landlord owned two UK properties, one of which had always been managed by a different agent. Management of one property later transferred to SJW UK Properties. Because the client had not told us about the other property, or that tax formalities had already been dealt with in the past, we initially handled the tax registration in the ordinary way. On further checking, we found that a separate tax record already existed. We then helped the client contact HMRC, verify the records and resolve the position.

In business since 2015: what gets lost is not the tax reference, but the information

What causes tax problems is usually not a failure to file. It is that the landlord:

 does not know they already hold a UTR;

 has forgotten that they once registered for tax;

 did not hand over the tax paperwork fully when changing managing agent;

 did not give the new accountant the complete set of HMRC documents.

A great many tax problems come down to incomplete information.

SJW Practical Tip

Based on our practical experience at SJW UK Properties, we recommend that overseas landlords build a complete HMRC tax file and keep it for the long term, including the UTR letter, the NRL approval letter, Self Assessment filing records, all HMRC correspondence, correspondence with the accountant and past tax returns. If you change managing agent or accountant, we also suggest providing these documents proactively, so that a duplicate tax registration is not created.

SJW Insight

Since 2015 we have become increasingly convinced that the UK tax system itself is not the difficulty. What needs managing is your own tax documentation. For an overseas landlord, acomplete HMRC file is often more valuable than remembering a tax reference. At SJW UK Properties we therefore always tell clients not to ignore or discard any letter from HMRC. A letter that looks unremarkable today may prove to be the key to resolving a tax issue years later.

Official References (as at July 2026)

This article is compiled from UK government and HM Revenue & Customs (HMRC) material, including:

 HMRC — Non-Resident Landlord Scheme (NRL)

 HMRC — Unique Taxpayer Reference (UTR)

 GOV.UK — Self Assessment

 GOV.UK — Non-Resident Landlord Scheme guidance

Last updated: July 2026

Disclaimer: This article draws on real cases at SJW UK Properties since 2015 and on UK tax practice. It is provided for general information only and does not constitute legal, tax or accounting advice. Circumstances differ from taxpayer to taxpayer. If you believe you may hold a duplicate UTR, or that there is an irregularity in your tax records, contact HMRC or a professional tax adviser as soon as possible for formal advice on your own position.