What split-year treatment actually does
The UK tax year runs from 6 April to the following 5 April. Under the Statutory Residence Test, you are either UK resident or non-UK resident for the tax year. Split-year treatment does not change that residence result. Instead, it divides a qualifying resident year into an overseas part and a UK part for certain tax purposes.
During the UK part, you are broadly taxed as a UK resident. During the overseas part, you are broadly treated as non-resident. That can make a significant difference to foreign income and gains arising before the UK part begins.
The five arrival cases
HMRC sets out eight split-year cases in total. Cases 1 to 3 concern people leaving the UK. For someone coming or returning to the UK, the relevant possibilities are Cases 4 to 8.
| Case | Typical trigger | Why it may matter to a returner |
|---|---|---|
| 4 | Starting to have only UK homes | Your overseas home has ended and all homes are now in the UK. |
| 5 | Starting full-time work in the UK | A qualifying 365-day period of full-time UK work begins. |
| 6 | Ceasing full-time work overseas | You return after a qualifying period of full-time overseas work. |
| 7 | Partner of someone in Case 6 | You move to the UK to continue living with a partner who stops full-time overseas work. |
| 8 | Starting to have a UK home | You establish a UK home but may still retain a home overseas. |
This table identifies the shape of each case, not all its conditions. Previous- and following-year residence, UK ties, home availability, day limits and work patterns can all be decisive.
Which case is most common when returning from Dubai?
There is no universal answer. For an employed British expat ending a Dubai role and returning permanently, Case 6 may be relevant. But it carries detailed conditions: the person must have been non-UK resident in the previous year because of full-time overseas work, must meet residence-history requirements, satisfy overseas-work criteria for the relevant period and be UK resident in the following year.
A person who starts a qualifying full-time UK role may instead meet Case 5. Someone establishing a UK home may meet Case 4 or Case 8, depending partly on whether an overseas home continues. A spouse or partner returning with the overseas worker may need to consider Case 7.
The split date may not be your flight date
This is where otherwise sensible planning can go wrong. Different cases use different statutory events to identify the end of the overseas part.
- Under Case 4, the UK part begins when the individual first meets the only-home test.
- Under Case 5, it begins with the first qualifying period of full-time work in the UK.
- Under Case 6, it begins after the final day of the latest period for which the overseas-work test is satisfied.
- Under Case 7, it begins on the statutory deemed arrival day.
- Under Case 8, it is linked to the date the individual starts to have a UK home.
If more than one arrival case applies, statutory priority rules determine the answer. For combinations of Cases 4, 5 and 8, the case producing the earliest split date can take priority. That can mean a shorter overseas part than expected.
A practical return example
Assume an executive finishes a Dubai role on 31 August, flies to the UK on 5 September, gains access to a permanent UK home on 10 September and starts a UK role on 1 October.
There are at least four dates in the story, but none should be declared the tax split date without testing the relevant cases. Case 6 may focus on the end of qualifying overseas work. Case 8 may focus on the UK home. Case 5 may focus on the start of a qualifying full-time UK-work period. If several cases are satisfied, the priority rules must then be applied.
The planning lesson is straightforward: before selling investments, taking pension benefits, receiving a large distribution or exercising share awards, confirm which part of the year the transaction will fall into.
What is—and is not—protected by the overseas part
Split-year treatment can prevent foreign income and gains arising in the overseas part from being taxed as though you were UK resident throughout. But “overseas part” does not mean “nothing is taxable in the UK”.
- UK-source income can remain within UK tax even during the overseas part.
- UK land and property gains have their own non-resident rules.
- Employment income and share awards may require allocation to workdays or service periods.
- Temporary non-residence rules can bring certain gains or income realised while abroad into charge when you return.
- Double-tax agreements and foreign tax credits may affect which country taxes an amount and how relief is given.
The new foreign income and gains regime
Since 6 April 2025, qualifying new UK residents who have been non-UK resident for at least ten consecutive tax years may be able to claim relief under the four-year foreign income and gains regime.
A split year still counts as a full year of UK residence when assessing that ten-year history and the four-year window. The overseas part can therefore reduce what needs to be brought into the UK charge, but it does not create an extra partial year of relief.
This interaction makes the residence timeline particularly important for long-term Dubai residents with foreign portfolios, business interests or overseas income.
What should be documented before the move?
- every UK entry and exit date;
- the final overseas workday and daily working hours;
- the date Dubai employment formally ends;
- when Dubai and UK homes are available, occupied, let or surrendered;
- the UK employment start date and expected working pattern;
- the movement dates of a spouse, partner and children;
- UK workdays and days on which more than three hours are worked;
- residence status for the preceding and following tax years;
- the dates of any intended investment, pension, property or company transactions.
A clean calendar and supporting documents are often more valuable than a retrospective explanation assembled many months later.
How is split-year treatment reported?
Where Self Assessment is required, the residence pages are used to report that split-year treatment applies, the relevant date and the applicable case or cases. The 2025/26 residence notes also require additional information where more than one case applies.
The tax return is the reporting stage, not the planning stage. The analysis should be completed before material transactions—not after the year has ended.
The planning point
Split-year treatment can be extremely valuable, but it is not a blanket “tax starts when I land” rule.
Establish residence first. Test every relevant split-year case. Apply the priority rules. Then map income, gains and major decisions against the resulting timeline.
The dates should drive the transactions—not the other way around.
