Understanding UK Split-Year Rules: The Ultimate Guide to Avoid the Numerous Pitfalls

The UK’s Statutory Residence Test (SRT) normally determines tax residence on a full tax-year basis, meaning an individual is usually either UK resident or non-resident for the entire tax year. We have discussed how the test works in a couple of articles on this site. Please refer to our summary article on SRT for a quick overview or head over to our previous article for an in-depth deep dive on SRT.

However, special “split year” rules can apply if someone leaves or arrives partway through a tax year, allowing that year to be treated as two distinct parts: a UK-resident part and an overseas (non-resident) part. For a high-level summary please refer to our previous article on split years and SRT. For a deep dive please read on.

Under split year treatment, you are taxed as a UK resident on worldwide income and gains during the UK part, and as a non-resident (UK tax on UK sources only) during the overseas part. This treatment is not elective – it applies automatically if your circumstances meet one of the defined cases in the legislation. It is therefore crucial to understand the qualifying conditions and pitfalls of each case in order to properly assess how an arriver or a leaver should be taxed in the UK in their first or last years in the country.

Overview of Split Year Treatment Cases

There are 8 specific cases under which a tax year may be split into UK and overseas parts. Cases 1 to 3 cover scenarios for individuals leaving the UK (last year of UK residence), and Cases 4 to 8 cover those coming to the UK (year of arrival). In all cases, the individual must first qualify as UK tax resident for the year under the SRT’s ordinary rules (if they were non-resident for the whole year, split year treatment is not needed). Broadly, the eight cases are:

• Case 1 – Starting full-time work overseas (leaver)
• Case 2 – Partner of someone starting full-time work overseas (leaver)
• Case 3 – Ceasing to have a home in the UK (leaver)
• Case 4 – Starting to have only a home in the UK (arriver)
• Case 5 – Starting full-time work in the UK (arriver)
• Case 6 – Ceasing full-time work overseas (returning to UK) (arriver)
• Case 7 – Partner of someone ceasing full-time work overseas (arriver)
• Case 8 – Starting to have a home in the UK (while retaining overseas home) (arriver)

Each case has detailed conditions that must be met to qualify for split year treatment, involving factors such as prior/following year residency status (continuity rules), employment duties and work hours, limits on UK visits or workdays, and the location of homes or family. Below, we explain Cases 1–3 (departures) and Cases 4–6 (arrivals) in depth, with a brief note on Cases 7–8, which are variations of the partner/home scenarios. We also highlight key conditions (e.g. full-time work tests, home acquisition, family moves) and common pitfalls that can inadvertently cause someone to lose split year status and be taxed as UK resident for the entire year.

Split Year when Leaving the UK (Cases 1–3)

When an individual leaves the UK partway through a tax year and will be non-resident thereafter, the SRT provides three main cases under which their departure year can be split. These generally require that the person was UK resident in the year of departure, becomes non-UK resident in the following year, and satisfies specific conditions from the date of leaving until the tax year-end. The UK part of the year runs from 6 April up to the day before the qualifying event (e.g. start of overseas work or departure date), and the overseas part runs from that event to 5 April next. The cases are:

Case 1: Starting Full-Time Work Overseas

This case applies when an individual leaves the UK to work full-time abroad. In general, the tax year will be split from the date the person starts their overseas employment. For example, if someone departs the UK on 1 September to begin a job abroad that continues into the next tax year, 1 September would normally mark the start of the overseas part (with 6 April–31 August being the UK part). Key conditions for Case 1 include:

• Full-Time Overseas Work: From the day after leaving the UK, the individual must work sufficient hours overseas on average (broadly an average of 35+ hours per week) with no significant breaks in employment (more than 31 continuous days). HMRC’s “sufficient hours” test is applied over the period from the start of overseas work to the end of the tax year to confirm full-time status. You should use the step-by-step calculation guide provided by HMRC to compute the weekly average.
• Limited UK Presence After Departure: During the overseas part of the year (from the start of the new job to 5 April), the individual must not exceed certain limits on time spent back in the UK. The maximum is 90 days in the UK (counting any day of presence), but this limit is pro-rated for the part-year from departure to 5 April. Similarly, there is a cap on the number of UK workdays (days on which more than 3 hours of work are done in the UK) – under the full-year SRT rules this is 30 days max, pro-rated for the split-year period. HMRC has a table showing the maximum number of days you can spend/work in the UK based on the date of departure. For example, someone leaving in December would need to spend less than 30 days and work less than 10 days in the UK in the period from December to April 5th.
• Continued Non-UK Residence: The individual must remain non-UK resident in the following tax year, typically by virtue of working full-time abroad for at least a whole tax year. In practice, this usually means they will need to meet the Third Automatic Overseas Test in the next tax year (working sufficient hours overseas with ≤30 UK workdays) so that they are definitively non-resident after departure. Being UK resident in the year after departure would generally disqualify split year treatment for the departure year.
• UK Resident in Previous Year: Another continuity condition is that the individual was a UK resident in the tax year immediately before the year of departure. (If they were already non-resident before leaving, different rules apply – in fact, if someone leaves very early in a tax year and is non-resident for that year, one might instead consider splitting the prior year.)

If all these conditions are met, Case 1 will split the tax year on the date the person starts the full-time overseas work (often the departure date or next day). The period from 6 April up to that date is the “UK part” (taxed as resident), and from that date to 5 April is the “overseas part” (taxed as non-resident). 

Case 2: Accompanying a Partner Overseas

Case 2 covers situations where an individual themselves may not be working abroad full-time, but they leave the UK to accompany a partner who is starting full-time work overseas. In essence, if your spouse or civil partner (or common-law equivalent) qualifies under Case 1, you can also qualify under Case 2, splitting the year at the same date. The logic is to extend split year treatment to a trailing spouse/partner who moves abroad to continue living with the primary worker. The conditions for Case 2 include:

• Partner’s Status: Your partner must meet the requirements of Case 1 (starting full-time work abroad) in the same tax year. In other words, they must be leaving the UK to work full-time overseas and will qualify for split year themselves. The partner’s overseas work is the trigger for both of you.
• Living Together: You and your partner must have been living together in the UK either in that tax year before departure or the previous tax year. Essentially, there should be an established household. (Partner in this context means a spouse, civil partner, or someone you live with as such.)
• Joining Them Overseas: You leave the UK to join your partner abroad and continue living together during their overseas assignment. The split year for you will usually start on the later of (a) the day your partner’s overseas work begins (their departure date) or (b) the day you actually leave the UK to join them, if that’s after. In practice, many partners travel together, but if one person follows later, the split for the follower starts when they depart.
• Only/Main Home Abroad: From the point you leave the UK, your only or main home must be outside the UK for the rest of the tax year. Essentially, once you’ve joined your partner abroad, you shouldn’t still have a principal home back in the UK. (If you left a UK home behind, it should be disposed of, rented out, or otherwise not available such that your main home is truly overseas.)
• Limited UK Visits: Any return visits you make to the UK after your departure must stay within the “permitted limit” – up to 90 days, scaled down for the part-year after you left. This is similar to Case 1’s day-count restriction. If, for example, you left halfway through the year, the 90-day limit would roughly halve to ~45 days for the remaining part of the year.
• Timing and Continuity: You must have been UK resident in the preceding tax year, and you must be non-UK resident in the following tax year. The following year non-residence will usually occur naturally if your partner continues to work abroad full-time and you stay with them (so you likely spend very little time in the UK in that next year). But it is an important condition – if you ended up back in the UK the next year, that could invalidate the split treatment.

When Case 2 applies, the overseas part of the year starts on the day your partner begins full-time work overseas or the day you actually depart to join them, whichever is later. From that date to year-end is the overseas part (you taxed as non-resident), and before that is the UK part. 

Case 3: Ceasing to Have a Home in the UK

If an individual does not qualify under Case 1 or 2 (no full-time work abroad, either personally or via partner), they might still get split year treatment when leaving the UK under Case 3 – stopping having any home in the UK. This situation often applies to someone who leaves the UK to move abroad long-term (perhaps to retire or live in another country) and in doing so gives up their UK home. The tax year will be split from the date the person ceases to have a UK home, provided further conditions are met. Important requirements for Case 3 are:

• Home in UK at Start, None Later: You must have had at least one home in the UK at the beginning of the tax year, and at some point during the year you permanently cease to have any home in the UK. After that point, you cannot have any home in the UK for the remainder of the tax year. “Ceasing to have a home” typically means you give up your UK residence – for example, you sell your house, or your lease ends and you leave with no intention of return. (Simply moving out without selling may count, but you must genuinely not have a home available in the UK thereafter.)
• Overseas Move: Usually, this goes hand-in-hand with moving your life abroad – your only home (or homes) will be in an overseas country after you leave. However, Case 3 doesn’t strictly require full-time work or joining family; it’s often used by those retiring abroad or relocating without immediate employment.
• Minimal UK Presence after Leaving: Once you have no UK home, you must be very careful about visits back to the UK for the rest of that tax year. You are allowed at most 15 days in the UK during the overseas part after your departure. Note that this 15-day cap in Case 3 is stricter than the 90-day (pro-rated) limits in Cases 1 and 2. Essentially, Case 3 expects that when you cut ties by giving up your home, you truly spend very little time back in the UK for the remainder of the year.
• Establishing a Foreign Residence: An additional “continuity” condition requires that by six months after you ceased to have a UK home, you have established a presence or residence abroad. Specifically, within that six-month window you must satisfy one of the following: (a) you become resident in another country under that country’s rules, or (b) you are present in a single foreign country at the end of each day for that entire six-month period, or (c) you have your only home (or all your homes) in one foreign country during that period. This rule ensures that your move was genuine – you didn’t give up a UK home and then drift without establishing yourself elsewhere. In practice, it means you should settle in one country after leaving (e.g. buy or rent a home abroad and spend your time there).
• Preceding/Future Year Status: As with the other cases, you need to have been UK resident in the previous tax year and non-resident in the following tax year. Being non-resident in the next year will typically happen if you truly emigrated and have no UK home (since you’ll likely spend < 16–46 days in the UK in that next year, ensuring non-residence). If you ended up becoming UK resident again the very next year, it calls into question whether you really left, so that would void Case 3.

When these conditions are met, Case 3 splits the year on the date you stop having your UK home. The day after that becomes the start of the overseas part. 

Split Year when Arriving in the UK (Cases 4–8)

For individuals who become UK resident partway through a tax year (for example, moving to the UK from abroad), the SRT provides five cases under which the arrival year can be split. In all these cases, the person is non-UK resident for the earlier part of the tax year and then becomes UK resident from a point in the year onward. Typically, the overseas part will run from 6 April up to the day before the qualifying arrival event, and the UK part will run from that event to 5 April. The person must have been non-UK resident in the prior tax year (to prevent someone who was already resident from claiming a split on arrival). Many arrival cases also require the individual to remain UK resident in the following year (to show their move is enduring). We will focus on Cases 4, 5, and 6 (common arrival scenarios), and then explain Cases 7 and 8 briefly:

Case 4: Starting to Have an “Only Home” in the UK

Case 4 applies when someone comes to the UK during the year and at some point establishes their only (or all) home(s) in the UK. The classic scenario is a person who relocates to the UK and makes it their sole home base. Under Case 4, the year is split from the date the individual first meets the “only home test” in the UK. The only-home test means either: (a) you have only one home and it is in the UK, or (b) if you have multiple homes, all of them are in the UK. In practice, case 4 often covers someone who acquires a UK home and no longer has a home elsewhere. Key conditions for Case 4 are:

• No UK Home at Start: At the beginning of the tax year, you did not have a home in the UK. (If you already had a UK home from 6 April, you wouldn’t use case 4; your situation might fall under normal full-year residency or possibly case 8 if you had overseas homes too.)
• Non-Resident Previous Year: You must have been non-UK resident in the tax year immediately before the year in question. Case 4 is intended for true newcomers or returnees after a period of non-residence, not someone who was resident in the prior year.
• Acquiring an Only UK Home: During the tax year, you acquire a home in the UK and that becomes your only home (or all homes are in UK) from that point onwards. For example, you move to the UK, buy/rent a house, and you do not maintain any dwelling abroad that would count as a “home”. As soon as this condition is satisfied and expected to continue, the split can start.
• Continue to Meet Only-Home Test: You must continue to have your home (or all homes) in the UK for the rest of that tax year and there is no explicit requirement to keep it the following year in Case 4 (though in practice you likely will). Notably, Case 4 does not require you to be UK resident in the following year (that condition was omitted for Case 4). It simply focuses on the year of arrival.
• Limited UK Ties Before Arrival: Prior to the point you established the UK home, you must not have already been UK resident. Specifically, in the part of the year before you met the only-home test, you should not exceed the SRT’s sufficient ties threshold for residency. In other words, during the period from 6 April up to your arrival/UK home date, your combination of days in the UK and UK connection factors (ties) should be below the level that would trigger residency. The SRT adjusts the day-count thresholds in proportion to the part-year; HMRC provides a table of reduced day limits for the pre-arrival period. For instance, if someone’s UK home started on 1 October, the maximum days and ties allowed from 6 April–30 Sept are scaled down (e.g. fewer than ~90 days with limited ties). This rule ensures you weren’t effectively resident before your official arrival.

If you satisfy these conditions, Case 4 splits the year on the date you first have only a UK home.

Case 5: Starting Full-Time Work in the UK

Case 5 is essentially the mirror of Case 1 – it applies when an individual comes to the UK to begin full-time employment here during the tax year. If you were non-resident before and then take up a full-time job in the UK, you can split the year from the date that UK work commences. Conditions for Case 5 include:

• Starting Full-Time UK Work: You must start working “full time” in the UK in the tax year. Full-time work in the UK is defined by the SRT similarly to the overseas test: broadly, an average of 35 hours per week (over a reference period), with no significant breaks, and with most workdays in the UK. One specific condition is that at least 75% of your working days from the start of your employment to the end of the year are UK workdays (days on which you work >3 hours in the UK). This ensures the role is predominantly UK-based after arrival.
• UK Resident for Year / Non-Res Previous: You need to become UK resident in that tax year (which will generally happen automatically once you start full-time work and stay here) and you must have been non-UK resident for the prior tax year. Like other arrival cases, this is intended for genuine newcomers (or returnees after a clear break in residence).
• No Early UK Residency (Pre-Arrival): For the portion of the year before you met the full-time work condition, you should not have been UK resident. In practice, this means in the months before your job started, you must stay below the SRT sufficient-ties thresholds (with day counts scaled appropriately). Essentially, similar to Case 4, you shouldn’t inadvertently trigger residency by spending too much time in the UK prior to your official work start. If you came for interviews or house-hunting trips, keep them brief.

When these are met, the UK part of the year begins on the day you start your full-time UK employment. The preceding period is treated as the overseas (non-resident) part. 

Case 6: Ceasing Full-Time Work Overseas (Returning to UK)

Case 6 covers individuals who had been living and working abroad and then return to the UK after ending their overseas employment. In many cases these are people coming off an expatriate assignment. To qualify, you must have been non-resident in the previous tax year by virtue of working full-time overseas, and that overseas work ceases in the year, prompting your return. In effect, Case 6 is the reverse of Case 1: it splits the year at the end of your overseas job. The conditions for Case 6 include:

• Non-UK Resident Previous Year (Full-Time Abroad): You must have been non-resident in the tax year before the year in question, and the reason for your non-residence was that you were working full-time overseas. In practice, that typically means you satisfied the third automatic overseas test in the prior year (worked sufficient hours abroad, ≤30 UK workdays, ≤90 days in UK) – so you truly were an expatriate worker.
• Cessation of Overseas Work: In the current year, that full-time overseas work ceases. This could be because your foreign assignment ended, you retired from the overseas job, or you were transferred back to the UK. The timing of this cessation will effectively be the split point (the last day of overseas work or the day before you resume life in the UK).
• Return to UK & UK Residency: Following the end of your overseas job, you return to the UK to live (even if not immediately the next day, generally you relocate back). You must become UK resident in the current tax year (which will happen once you’re back and have sufficient presence or ties), and also you must be UK resident in the following tax year. The requirement to be resident in the next year ensures that the return is lasting, not just a temporary visit. Essentially you’re resettling in the UK.
• Limits on UK days before return: During the part of the year before your return (while you were still abroad working), you must continue to meet the conditions that kept you non-resident. Concretely, from 6 April up until the day your overseas work ends, you should have spent fewer than 90 days in the UK, pro-rated if the period is less than a full year. You also must have no more than 30 UK workdays in that pre-return period (pro-rated if necessary). These mirror the criteria of the overseas work test, scaled to part of a year. Essentially, you shouldn’t accidentally re-trigger UK residency before your job ended by spending too much time working or living in the UK.

If these conditions are met, Case 6 treats the year as split: the overseas part runs from 6 April up to the last day of your full-time overseas employment, and the UK part starts from the day after that (when effectively you are free from the job and can settle in the UK). 

Example: Priya has worked in Singapore for several years. She was non-UK resident in 2024–25 (qualifying via full-time overseas work). Her assignment ends on 30 November 2025, and she moves back to the UK in December 2025 to take up a new position. She ensured she took minimal trips to the UK before November (say 40 days and 10 workdays from April–Nov, within limits). Priya meets Case 6. The split year starts 1 December 2025 (UK part from that date, as she resumes UK residence; overseas part 6 April–30 Nov while she was working abroad). Had Priya returned on a break to the UK for too long before 30 Nov or worked remotely from the UK during her notice period such that she exceeded the day/workday limits, she might inadvertently become UK resident earlier in the year, jeopardizing the split. Likewise, if after finishing her overseas job she didn’t actually move to the UK (say she traveled elsewhere or delayed coming to the UK until the next tax year), she might not fulfill the requirement of becoming UK resident in 2025–26 – potentially negating the split treatment.

Case 7: Returning to the UK with a Partner (Partner of Case 6)

This case is analogous to Case 2, but on the returning side. Case 7 applies if your partner’s overseas full-time work ends (Case 6) and they come back to the UK, and you move to the UK to join/rejoin them in the same tax year. In other words, if your spouse or partner satisfies Case 6 in a given year (or satisfied it in the prior year), you, as the accompanying partner, can also claim split year from when you come back together. Key conditions for Case 7:

• Partner Qualifies under Case 6: Your spouse/civil partner (or equivalent) must meet the criteria of Case 6 – i.e. they were non-resident last year due to full-time work abroad, that work ceases this year or ceased late last year, and they are becoming UK resident again. Essentially, your partner is in the process of a Case 6 split (either in the same year or perhaps they returned right at the end of last year with a split then).
• Moving to Live Together in UK: You move or return to the UK to continue living with your partner once they come back. The intention is that you resume your life together in the UK. The split year “deemed arrival day” for you will be the later of the day your partner becomes UK resident under Case 6 and the day you yourself arrive in the UK to join them. Practically, if you travel back together, that date is your joint arrival; if one comes slightly later, the later date is used.
• Non-Resident Previous Year: You must have been non-UK resident in the prior tax year (which likely you were if living abroad with your partner during their assignment).
• UK Resident Current and Next Year: You need to be UK resident for the current year (once reunited in the UK) and also UK resident in the following tax year, to demonstrate that you’ve resettled in the UK long-term.
• Home and Time Before Arrival: Before your deemed arrival day, you must not have been essentially living in the UK. Specifically, during the part of the year before you moved back, either you had no home in the UK, or if you did have a UK home, you also had an overseas home and spent the majority of your time living abroad. This prevents someone who was already partly living in the UK from using Case 7. In practice, many accompanying partners will have had no UK home while abroad (so the first condition is satisfied), or if they maintained a UK house they didn’t live in it (spent more time overseas).
• Limited UK Visits Pre-arrival: Similar to other cases, you must not exceed the proportional limit of 90 days in the UK before your arrival. The 90-day limit is scaled for the shorter period if necessary. Essentially, while your partner was finishing overseas work and before you moved back, your visits to the UK should have been minimal so as not to trigger residency on your own.

If all conditions align, Case 7 splits the year for you from the “deemed arrival day”, as defined (joining your partner on their return). 

Case 8: Starting to Have a Home in the UK (While Retaining Overseas Home)

Case 8 is a slightly nuanced arrival case, introduced to cover situations where someone acquires a UK home during the year but does not give up their overseas home (so they do have a home outside the UK concurrently). It is similar to Case 4, with a few extra continuity requirements. To qualify for Case 8, an individual must start to have a home in the UK during the year (having had none at the start) and maintain that UK home into the next year. The conditions are:

• No UK Home at Start: You had no home in the UK at the beginning of the tax year (same as Case 4’s starting condition).
• Acquire a UK Home Mid-Year: At some point in the year, you acquire a home in the UK (e.g. purchase or begin to occupy a residence). From that point, you have a UK home.
• Retain UK Home for Remainder and Next Year: You continue to have that UK home for the rest of the tax year and for the entire following tax year, and you are UK resident in the following tax year. This is a crucial distinction of Case 8 – it demands that the UK home be kept and that you actually stay UK resident the next year (the year after arrival must not itself be a split year; it should be a normal resident year). This ensures the UK home was not a short-term or transient arrangement.
• Previous Year Non-Resident: As with all arrival cases, you must have been non-UK resident for the prior tax year.
• Limited UK Ties/Days Pre-home: From 6 April up until the point you acquired the UK home, you must not have had sufficient UK ties to be resident. Essentially the same rule as Case 4: during the period before you had any UK home, your UK days and ties must be kept under the thresholds (with day count limits scaled as per HMRC’s table). You should not be “resident” earlier in the year before getting the UK home.

Notably, Case 8 does not require that the UK home be your “only” home. You could still own or maintain property abroad – those overseas homes are irrelevant for Case 8’s primary condition. This means Case 8 is designed for someone who might start splitting time between countries. For instance, an individual could buy a flat in the UK mid-year but also keep their house in their original country. Provided they weren’t UK resident before acquiring the UK home and they commit to keeping that UK home and staying resident going forward, they can split the arrival year under Case 8. The split date will be the day you start to have a UK home.

 To summarize cases 4–8: these allow a new UK resident to only be taxed as UK-resident from the point their circumstances change (home or work or partner’s return) rather than from the start of the tax year. Cases 4 and 8 both deal with acquiring homes in the UK (with Case 4 requiring it to be your only home, Case 8 allowing multiple homes). Case 5 covers starting work in the UK, and Case 6 covers returning after working abroad. Case 7 is the accompanying partner of a Case 6 returner. All require the prior year to be non-resident and generally that the move is a permanent or long-term one (as evidenced by continuing status the next year).

Finally, note that if by chance more than one case could apply (for example, someone starts full-time work in the UK and also meets the only-home condition around the same time), the legislation has a priority ordering to determine which case takes precedence. This is important because it fixes a single split date. The priority (in brief) is: Cases 1–3 override others if leaving; for arrivals, Case 4 (only home) tends to take precedence unless Case 5 (work) started earlier, etc., and Case 8 is somewhat a catch-all if others don’t apply. In most scenarios, only one case will clearly fit.

Key Conditions to Qualify for Split Year

The case-by-case details above highlight several common conditions that practitioners should watch for when determining if split year treatment applies:

• UK Residence in Split Year: The individual must be UK resident for the tax year in question (by the normal SRT tests). If they are not resident at all for that year, split year is moot. Conversely, if they are resident, one then tests for split year cases. Importantly, if they fail all split year cases, they remain UK resident for the entire year by default.
• Non-UK Resident in Adjacent Year(s): Many cases require a specific residency status in the preceding and/or following tax year as a continuity rule. For leavers (Cases 1–3), you generally must have been UK resident in the prior year and become non-resident in the next year. For arrivers (Cases 4–8), you usually must have been non-resident in the prior year, and some cases require you to be resident in the following year to show permanence. These continuity rules are critical – failing them can deny split treatment even if the within-year event occurred. Always verify the status of the year before and after.
• “Sufficient Ties” and Day Counts in Pre-Arrival/Post-Departure Periods: Each case imposes limits on how much time can be spent in the UK outside of the “home” or “work” period. For someone leaving (Cases 1–3), any return visits after their departure must be within permitted day counts, and UK workdays must be minimal. For someone arriving (Cases 4–8), their presence before the arrival event must not trigger residency – typically meaning they stayed under 91 days and managed their UK ties so as not to meet the sufficient-ties test. HMRC provides scaled day limits for partial-year calculations of ties (for example, if arriving halfway, the threshold for “too many days” is lower).
• Full-Time Work Tests: In Cases 1 and 6 (and by extension 2 and 7 via a partner) the notion of “full-time work” is crucial. HMRC defines this with a formula: average 35 hours/week over the “reference period” with no significant break, plus not exceeding 30 UK workdays in a tax year (prorated if needed). The individual must meet the sufficient hours overseas test (for Case 1) or the analogous test for UK work (for Case 5) or have met it in the prior year (for Case 6 eligibility). Be mindful of what counts as a “workday” (more than 3 hours of work) and what constitutes a “significant break” (generally a period of 31+ days with no work or only minor breaks like annual leave don’t count as breaking continuity). Proper record-keeping of work patterns is essential, as a shortfall in hours or an extra workday in the UK can tip the balance.
• Home in the UK or Abroad: Cases involving homes (Case 3 for leavers, Cases 4 and 8 for arrivers) have very specific housing-related conditions. For Case 3, the individual must truly rid themselves of any UK home and then stay abroad. For Cases 4 and 8, the individual must secure a UK home and, in Case 4, not maintain any foreign home concurrently. In Case 8, they can keep overseas homes, but they need to hang onto the UK home into the next year. “Home” has a particular meaning in the SRT (essentially a place available to live on a long-term basis). Overlooking an available property (for example, a house left empty in the UK might still count as a home unless it’s genuinely no longer usable by you) can lead to failing a condition. Similarly, acquiring a home abroad is implicit in Case 3’s six-month rule – after leaving the UK, the person should have a tax residence or home somewhere else.
• Family/Partner Moves: Cases 2 and 7 involve accompanying a partner, which requires confirming the couple’s situation. They must be genuinely living together and both moving in tandem (first one as the primary worker, then the other following). The partner’s status is a precondition (if the working partner fails their case, the accompanying partner’s split year fails too). Additionally, if the partner lagged in moving, the dates have to be handled carefully. Make sure to document that the move was “to continue living together” and that any delay between partner’s move and the individual’s move is within the same year and aligns with the conditions.

In practice, determining eligibility often means working through a checklist for the specific case and verifying all pieces: prior year status, following year plans, exact date of moving or job change, number of days in UK before/after, ties (like family, accommodation) before/after, and so on. It’s wise to refer to HMRC’s guidance (e.g. the internal manuals or RDR3) for each case’s fine print, as the legislation is detailed. Missing one condition – for example, spending 16 days in the UK instead of 15 after selling your house – can mean no split year treatment, with significant tax consequences.

Common Pitfalls That Can Jeopardize Split Year Status

Despite the clear-cut rules, individuals frequently fall into traps that cause them to lose split year treatment or inadvertently remain UK resident for the entire year. As advisors, being alert to these pitfalls is crucial:

• Exceeding Day Limits (“One Day Too Many”): The SRT split year cases come with hard thresholds on days and ties. One of the most common errors is miscounting or misplanning days in the UK. Spending just a single day more in the UK than allowed can nullify the split year claim – there is no de minimis tolerance. For example, an individual leaving for full-time work abroad who is permitted 30 UK workdays and inadvertently works 31 days in the UK has broken the Case 1 conditions. Similarly, exceeding 15 days post-departure in a Case 3 scenario by even 1 day will fail the test. Accurate day counting and leaving buffer room (don’t push right up to the limit) are essential.
• Too Much Work in the UK: Relatedly, working too many days in the UK or doing substantive work during what was supposed to be the “overseas” period is a pitfall. In Cases 1 and 6, the 30-day UK workday limit is strict. It’s easy for business travelers to unintentionally trigger a workday (e.g. checking work email or having a call could count if it exceeds 3 hours). In Case 5 (arrivers), starting to do work in the UK before your official start date could make you resident earlier. Always align work start/stop dates with the intended split date and caution clients against any work activities in the UK outside the UK-resident portion. Keep detailed records to distinguish workdays from personal days.
• Brief Returns or Extended Visits to the UK: Someone may plan an overseas move but “pop back” to the UK too often or for too long, undermining their non-resident period. For instance, after leaving the UK for a job abroad (Case 1), coming back for a few weeks of remote work or personal matters might seem harmless, but if it breaches the permitted days, the individual becomes fully UK resident. We often see clients underestimating how days add up (arriving late one night and leaving early still counts as 2 days in HMRC’s eyes due to presence at midnight rule). If an emergency or unexpected need arises causing a longer UK stay, be prepared to reassess residency status.
• Gaps Between Jobs or Broken Contracts: Split year Cases 1 and 6 assume a continuous period of full-time work (outbound or inbound). If a client quits or loses their overseas job early, or there’s a significant gap between ending one job and starting another, this can wreck the split. For example, a person leaves the UK for a job abroad, but the job ends after 3 months and they don’t find new overseas employment – they will fail the “full tax year overseas work” requirement and might remain UK resident for that year (since they didn’t actually maintain non-residence into the next year). 

• Overlapping or Retained Accommodation (“Accommodation Tie” issues): Housing arrangements are a frequent source of trouble. Under Case 3, some individuals mistakenly think moving abroad and leaving their UK house empty is enough. But if that house remains available for their use, HMRC may still count it as a “home” (triggering an accommodation tie and possibly disqualifying Case 3). One must truly cease to have a UK home – ideally by selling, terminating a lease, or renting it out to someone else such that you can’t freely live there. Failing to do so could mean HMRC says you never lost your UK home, so Case 3 doesn’t apply. On the flip side, for Case 4, having an overseas home at the same time as acquiring a UK home means it’s not your “only” home – you’d fail Case 4 and might need to use Case 8 or be fully resident earlier. 

• Failing Next-Year Tests: Some cases hinge on what happens in the following tax year. For instance, Cases 1 and 2 require that the individual is non-resident in the year after departure. Cases 6, 7, 8 require being resident in the year after arrival. If your situation changes such that you don’t meet the expectation in the next year, HMRC can retroactively deny the split. For example, someone leaves the UK in Feb 2025 for a supposed 2-year job (uses Case 1 for 2024–25), but then they return in October 2025 for a new UK job, making them UK resident in 2025–26. They failed the “non-resident the next year” condition – thus 2024–25 would likely be viewed as UK resident full year. If there’s uncertainty about staying non-resident or staying in the UK, understand the risk. Sometimes timing a move a few months earlier or later to ensure a full clean year of non-residence/residence can protect the split claim. If next-year residency status does end up contrary to plan, be prepared to revisit the tax position for the split year and possibly amend filings.

Overall, thorough planning and monitoring are the best defenses against these pitfalls. You need to keep detailed travel logs, work records, and housing documentation. Mid-year moves are inherently complex – small mistakes (an extra meeting in London, a flat that wasn’t sold in time, etc.) can have outsized effects on tax residency.

UK Tax Implications of Split Year Treatment

When split year treatment applies, it can significantly limit an individual’s UK tax exposure on foreign income and gains, because part of the year is treated as a period of non-residence. It’s important to understand which income/gains fall into the UK part vs. overseas part, and how those are taxed, as well as the implications for domicile-based rules like the remittance basis or deemed domicile status.

• Income Tax – UK Part vs Overseas Part: In the UK-resident part of the split year, the individual is taxed like any UK resident: generally liable to UK Income Tax on their worldwide income (from UK and foreign sources). In the overseas (non-resident) part, the individual is taxed as a non-resident, meaning they are liable only on UK-source income and not on foreign income. Any income arising from sources outside the UK during the overseas part is outside the scope of UK tax. For example, salary from an overseas job earned after your departure, or interest on a foreign bank account received in the overseas period, would not be taxed by the UK. However, UK-source income (like UK rental income or UK work income) remains taxable in the UK even if received during the non-resident portion – UK source is always taxable by the UK regardless of residency. Timing can be used strategically: if possible, income can be accelerated or delayed to fall into the non-taxable window. One should be mindful of anti-avoidance rules like temporary non-residence: certain types of income, e.g. some dividends from close companies or pension withdrawals taken while non-resident, can be clawed back if the non-residence period is too short – typically less than 5 full years out.
• Capital Gains Tax: The split year treatment also applies to Capital Gains Tax (CGT) in a parallel way. During the overseas part of the year, the individual is treated as non-resident, and no UK CGT is due on disposals of assets in that period (except for specific cases like UK land or property, since non-residents are liable for UK property gains). Gains on foreign assets realized while non-resident are not taxed by the UK. In the UK-resident part, gains on worldwide assets are taxable as normal for a resident. This can create planning opportunities: for example, someone planning to leave the UK might defer selling a valuable asset until after their departure date so that the sale occurs in the overseas part of the split year, escaping UK CGT. Conversely, someone arriving might choose to realize gains before becoming UK resident. Take care again with the five-year rule for temporary non-residents: if an individual sells certain assets while non-resident and returns to UK residency within 5 years, the gain can be taxed on return (this rule catches capital gains of people who take short non-resident breaks) – split year does not exempt one from that, as it looks at the whole period of non-residence across years. Additionally, if a gain relates to a UK property, non-residents are liable for that anyway (though principal residence relief might apply if it was their home). The main point: splitting the year means foreign gains before arrival or after departure aren’t taxed, giving partial-year newcomers/leavers a chance to rebalance portfolios or withdraw investments free of UK CGT.
• Dual Residency and Treaties: Sometimes a split year individual will also be considered resident of another country for part or all of the year (e.g. in Cases 1–3, during the overseas part they likely become resident of their new country). This can lead to dual resident status for that overlap period. The UK has many double tax treaties which contain tiebreaker rules to assign a single residency for treaty purposes. While beyond the scope of this guide, be aware that a treaty might override domestic law treatment of certain incomes. One should consider treaty relief to avoid double taxation – for example, if the UK part and overseas part result in both countries taxing some income, the treaty or foreign tax credits may alleviate the burden. The good news is that split year treatment itself already narrows the overlap: you’ll only be UK resident for the portion where presumably you were non-resident elsewhere, and vice versa. For instance, someone who becomes UK resident from October will likely be treated as non-resident in their old country after October under that country’s rules, meaning less overlap. But if overlap exists (e.g. you meet residency tests of both countries in the overlap month), use the treaty to prevent double taxation.
• Loss of Personal Allowance or Other Partitioning: One might ask: does the personal allowance or tax bands split by period? No – the split year treatment doesn’t apportion allowances or rate bands; those apply for the full tax year’s income that is taxable in the UK. Practically, since foreign income from the overseas part is not taxed at all, it’s just not reported. But any UK-source income that spans the split (like UK bank interest paid through the year) remains taxable, albeit you might allocate it between resident and non-resident periods in terms of application of reliefs. Generally, income earned in the UK part is taxed with full annual allowances available. There’s no concept of half an allowance because you were resident half the year – you’re treated as resident for the year for allowance purposes (unless you are non-resident for the whole year, in which case some UK income like pure investment might not get a personal allowance for non-residents unless treaty, but in a split year you are resident, so you do get allowances).

Tax planning around split years: One should be proactive in timing income and gains around the split point. For leavers, if possible, accelerate foreign income and gains into the post-departure period, and defer UK-source income to before departure if it might not be taxed later (or just be mindful of split). For arrivers, consider realizing gains or taking income before becoming UK resident (for example, paying yourself a bonus or dividends from your company in your home country just before moving) so that the UK won’t tax it. Also consider foreign tax implications: you may become taxable in the other country for that period, so coordinate the plan (maybe that country has lower or no tax on a certain gain). 

Conclusion

The Statutory Residence Test’s split year provisions are a crucial aspect of UK tax for internationally mobile individuals. For professionals advising on these rules, it’s important to analyze each case’s conditions in detail, ensure the individual’s facts align exactly, and plan around those conditions. Pay special attention to continuity requirements, day counts, and behavior during transition periods to avoid unintended full-year residency. When applied correctly, split year treatment can mitigate UK taxation on foreign income and gains for part of the year, offering relief and fairness for those genuinely leaving or coming to the UK. But getting it wrong can have costly outcomes – either a loss of the split (with worldwide tax for the whole year) or potential challenges from HMRC. Always document your pattern of life carefully (work, homes, family location, travel) to support the split year position in the file.