UK Tax Residency and Double Taxation Agreements (DTAs)

Understanding UK tax residency is vital when moving to or from the UK. If you are relocating or returning, understanding how HMRC determines your tax residency can help you avoid unnecessary tax liabilities. The Statutory Residency Test (SRT), along with split year treatment, plays a crucial role in this process. Additionally, Double Taxation Agreements (DTAs) help resolve tax residency conflicts between countries, ensuring you don't pay tax twice on the same income.

In this guide, we'll explain the Statutory Residency Test, the workings of split year treatment, and how Double Taxation Agreements (DTAs) provide protection for individuals facing dual tax residency.

Table of Contents

• What is the Statutory Residency Test (SRT)? 

  • 1. Automatic UK Resident Test 

  • 2. Automatic Overseas Test 

  • 3. The Tie-Based Test 

• What is Split Year Treatment? 

• Case Study: Amelia’s Return to the UK After Working in the US 

• Double Taxation Agreements (DTA) 

• How Does a DTA Help? 

• Key Takeaways 

• Conclusion 

What is the Statutory Residency Test (SRT)?

The Statutory Residency Test (SRT) is used by HMRC to determine your UK tax residency status. Your residency status determines whether HMRC taxes you on your worldwide income or only on income sourced from the UK. The test has three key components: 

1. Automatic UK Resident Test

You will automatically be a UK resident if any of the following apply: 

• You spend 183 days or more in the UK during the tax year (6 April to 5 April). 

• You have a home in the UK and spend more than 30 days in the UK during the year. This rule also requires that you have no overseas home or spend fewer than 30 days in an overseas home. 

• You work full-time in the UK for a continuous period of 365 days or more, with no significant breaks. 

2. Automatic Overseas Test

You will automatically be a non-resident if: 

• You spend fewer than 16 days in the UK during the tax year. 

• You were not a UK resident in any of the previous three years. 

• You are not a UK citizen, or you are a UK citizen but spend fewer than 46 days in the UK. 
  

3. The Tie-Based Test

If you do not meet the conditions for automatic residency or non-residency, HMRC uses a tie-based test. This considers your ties to the UK, such as:

• Family

• Work

• Accommodation

• The number of days spent in the UK
  

The more ties you have, the fewer days you can spend in the UK before being classified as a tax resident.

For detailed information, refer to HMRC's Residency Guidelines.

What is Split Year Treatment?

Split year treatment allows HMRC to treat you as a UK tax resident for only part of the tax year. This is especially relevant if you move to or leave the UK mid-year. If you qualify for split year treatment, you’ll only pay UK tax on your income from the date you become a UK resident, or from the date you leave the UK, depending on your situation. 

Split year treatment ensures HMRC doesn't tax you on income earned before you become a UK resident or after you leave.

When Does Split Year Treatment Apply?

Split year treatment is applicable when: 

• You arrive in the UK during the tax year and were a non-resident before that. 

• You leave the UK during the tax year and were a UK resident before leaving. 

• You meet the Sufficient Hours Test for work done overseas, making it applicable even if you move abroad for employment purposes. 

The rules are specific, and you need to meet certain criteria to benefit from split year treatment. 

Case Study: Amelia’s Return to the UK After Working in the US

Background:  Amelia, a cartographer, worked in the US from 2018 to 2024. In early 2024, her company offered her a role back in the UK, and Amelia moved to London on 1 June 2024. Before her move, Amelia had been living and working in the US for several years, with no significant ties to the UK. 

Statutory Residency Test: 

• Before 1 June 2024: Amelia was a non-resident in the UK. 

• From 1 June 2024: Amelia becomes a UK resident when she starts her new role in the UK. 
  

Split Year Treatment Calculation:

Since Amelia moved in June, her tax year is split as follows:

• Period 1 (6 April 2024 to 31 May 2024): Non-resident, working in the US.

• Period 2 (1 June 2024 to 5 April 2025): Resident, working in the UK.
  

The Sufficient Hours Test:

To qualify for split year treatment, Amelia must meet the Sufficient Hours Test for her overseas work. This test ensures she did the majority of her work outside the UK during the period she was non-resident.

Let’s assume Amelia worked 300 hours between 6 April 2024 and 31 May 2024. Amelia works a standard 5-day workweek. Over the course of this period, there are 56 days (from 6 April to 31 May). 

Since Amelia works a typical 5-day workweek, she has worked for 40 days (8 weeks × 5 days). Let’s calculate her average number of hours worked per day: 

300 hours40 workdays=7.5 hours per day300 hours40 workdays=7.5 hours per day.

Since Amelia works 7.5 hours per day, well above the 3-hour minimum the Sufficient Hours Test requires, she qualifies for split year treatment.

Final Tax Residency Status for Amelia

• Amelia is non-resident in the UK from 6 April 2024 to 31 May 2024. 

• Amelia is a UK resident from 1 June 2024 onwards. 
  

Therefore, Amelia qualifies for split year treatment, meaning she will only be taxed on her UK income from 1 June 2024, and her income earned while working in the US will not be taxed in the UK. 

Double Taxation Agreements (DTA)

What if you are considered a tax resident in more than one country, as Amelia might be, depending on her ties or activities elsewhere?  

This situation can lead to dual residency—being considered a resident in both the UK and another country. Fortunately, the UK has Double Taxation Agreements (DTAs) with several countries to help resolve dual residency issues. 

HMRC publishes a complete list of tax treaties, which include agreements with various countries around the world. 

This is an area we assisted many clients over the self-assessment reporting period last month (January 2025). 

How Does a DTA Help?

The DTA between the UK and US, for example, outlines how income will be taxed when an individual is considered a tax resident in both countries. The agreement ensures that you do not pay tax twice on the same income. Typically, the DTA contains a tiebreaker rule to determine which country has the right to tax you. The tiebreaker rule considers various factors such as: 

• Permanent Home: Where is your permanent home located? 

• Centre of Vital Interests: Where are your economic and personal ties strongest? 

• Habitual Abode: Where do you spend most of your time? 

• Nationality: Which country are you a citizen of? 

Once your primary residency is determined under the DTA, you will usually only be taxed in that country, while the other country will grant you relief (often in the form of a foreign tax credit) to prevent double taxation. 

If Amelia had been considered a resident of both the US and the UK, the US-UK DTA would help determine where her income is taxed, ensuring she is not taxed twice. It would also likely allow Amelia to claim relief in one of the countries through a foreign tax credit or exemption, depending on the terms of the agreement. 

Key Takeaways

• The Statutory Residency Test (SRT) helps determine your UK tax residency status, which is crucial for understanding how your income will be taxed. 

Split year treatment allows you to be considered a UK tax resident for only part of the year if you move to or leave the UK mid-year. 

• The Sufficient Hours Test ensures that income earned while working abroad is not taxed in the UK if you meet specific requirements. 

• If you are considered a tax resident in more than one country, Double Taxation Agreements (DTAs) provide relief from being taxed twice, typically by designating one country as your primary residency. 
  

Conclusion

The Statutory Residency Test (SRT)

is essential for determining your UK tax residency status. By understanding the automatic residency tests, the tie-based test, and how split year treatment works, you can ensure that you’re taxed fairly and avoid unnecessary tax liabilities. 

If you are dual resident due to spending time in both the UK and another country, the Double Taxation Agreement (DTA) helps resolve which country has the right to tax your income. It’s always advisable to consult with tax professionals to navigate the complexities of residency and taxation and avoid double taxation. 

For expert advice on UK tax residency and planning, feel free to visit ASWATAX UK Tax Advice page.

Meet Omar Omar is a Chartered Tax Advisor (a.k.a an expert on tax issues) and founder of ASWATAX. He regularly shares his knowledge and best advice here in his blog and on other channels such as LinkedIn. Book a call today to learn more about what Omar and ASWATAX can do for you.