Leaving the UK tax residency system is a three-part exercise: exit cleanly in the departure year, keep your UK days under the right limit every year after, and avoid coming back inside five years with gains in your pocket. Get all three right and HMRC's claim on your worldwide income ends at the airport. Get one wrong and you can be resident again without ever moving back. Here is how leavers actually stay left.
Split year treatment: how the departure year divides
UK tax residence is normally all-or-nothing for a tax year (6 April to 5 April). But in the year you leave, split year treatment can divide it into a UK part and an overseas part, so your foreign income after departure escapes UK tax. For leavers there are three main cases:
- Starting full-time work overseas - roughly 35 hours a week on average abroad, with UK visits kept under the pro-rated day and workday limits;
- Joining a partner who has started full-time work overseas; or
- Ceasing to have a UK home - you give up your UK home, establish your home abroad, and spend only minimal days in the UK afterwards.
Split year treatment is automatic when the conditions are met, not elective - and every case requires you to actually be non-resident for the following full tax year. Leavers who drift back over the day limits in year two lose the split retroactively, which is exactly the failure a day tracker prevents. If you leave without needing to file a return, tell HMRC with form P85; otherwise the split is claimed in your Self Assessment.
Your day limit after leaving depends on your ties
As a "leaver" (resident in at least one of the previous three tax years), the sufficient ties test sets your personal UK day budget. Count your ties - family in the UK, available accommodation, 40 or more UK workdays, 90-plus days in either of the two previous years, and the leaver-only country tie (more days in the UK than any other single country) - then stay under the matching limit:
- 4 or more ties: fewer than 16 UK days;
- 3 ties: fewer than 46 days;
- 2 ties: fewer than 91 days;
- 1 tie: fewer than 121 days.
Days are counted at midnight, with a deeming rule that can pull in transit-style days for frequent returners. Notice the design: most recent leavers start with the 90-day tie automatically, so the practical budgets in the first two years are tighter than people expect. The full-time work overseas route replaces all of this with its own limits - under 91 UK days, of which fewer than 31 workdays - as long as the 35-hours-a-week average holds.
The five-year rule: do not come back rich too soon
Leaving also starts a clock. If you return to UK residence within five years, the temporary non-residence rules tax you on arrival for much of what you realised while away: capital gains on assets you already owned at departure, certain dividends from your own company, and similar income crystallised in the gap years. Sell the business from Lisbon in year three, move back in year four, and the gain lands in your UK return as if you had never left. If a return is even possible, plan disposals against the five-year clock - or make the move genuinely long-term.
One more reason precision matters now: since 6 April 2025 the old non-dom regime is gone. Residence alone drives exposure to UK tax on worldwide income and gains, with only a short foreign-income window for genuinely new arrivers. For a returning leaver there is no remittance basis to fall back on - the day count is the whole game.
Track your exit like HMRC would check it
Every element above - the split date, the following-year non-residence, the tie-based budget, the five-year clock - is evidenced by where you actually were. Tax Residency Tracker keeps that record:
- Set the custom tax year to 6 April so every count matches HMRC's year, not the calendar.
- The Midnight Rule counting mode counts days the way the SRT defines them - where you were at the end of the day.
- A custom UK threshold alert at your personal limit (15, 45, 90 or 120 days) warns you before a family emergency or a long summer quietly makes you resident again.
- Planned-stay previews price a return visit against the budget before you book.
- The dated location history plus attached documents (P85 confirmation, tenancy surrender, boarding passes) are exactly the evidence an HMRC residence enquiry asks for, and CSV export hands it over cleanly - all stored on your device.
Frequently asked questions
Do I have to tell HMRC that I left?
If you normally file Self Assessment, you claim the split and non-residence in your return. If not, form P85 tells HMRC you have left and sorts any refund of overpaid PAYE for the departure year.
How many days can I spend in the UK after leaving?
It depends on your ties: under 16 days with four or more ties, under 46 with three, under 91 with two, under 121 with one. Under 16 days keeps a recent leaver non-resident regardless of ties.
What breaks split year treatment?
Failing the following-year test is the classic: every leaver case requires you to be non-resident for the next full tax year, so creeping back over your day limit in year two unwinds the split itself.
Does the five-year rule catch salary earned abroad?
No - ordinary employment income earned while genuinely non-resident stays out. The rule targets gains on assets you held at departure and certain income like close-company dividends realised during the temporary absence.
Start with the test itself in the UK Statutory Residence Test, get the day definitions right in how to count days for tax residency, see how treaties resolve dual claims in tax treaty tie-breaker rules, or browse all guides.