Two numbers get conflated constantly: the "UK days" that decide whether the Statutory Residence Test makes you UK resident, and the "overseas workdays" that source your OWR relief once you already are. They're counted completely differently, and the SRT side has a rule — the deeming rule — that can inflate a day count well past what a naive midnight tally would suggest.
The midnight rule, first
By default, a day counts toward your UK day total only if you're in the UK at midnight at the end of it. Arrive and leave same-day without being here at midnight, and it doesn't count — with an exception for genuine transit days (arriving as a passenger and leaving the next day without doing anything unrelated to passing through). Days you're in the UK due to exceptional circumstances beyond your control — HMRC's examples include illness that prevents travel, civil unrest, natural disasters, and war — still count, up to a maximum of 60 such days in a tax year.
When the deeming rule switches on
The deeming rule exists specifically to stop people gaming the midnight rule with short, frequent same-day trips. It applies once you meet all three of these conditions for the tax year:
- You were UK resident in at least one of the preceding 3 tax years.
- You have 3 or more UK ties for the current tax year (the 90-day tie calculation for this purpose only counts actual midnight-present days, not deemed ones).
- You've been present in the UK on more than 30 days in the tax year without being present at midnight.
Meet all three, and every qualifying day beyond the first 30 — not the first 30 themselves — gets added to your midnight-day total. HMRC's own worked example: someone present at midnight on 44 days, and present but not at midnight on a further 50 days. Since 50 exceeds 30 by 20, those 20 extra days get added: 44 + 20 = 64 total UK days, not 44. The deeming rule does not apply to anyone who meets the third automatic overseas test for the year.
The 5 UK ties, briefly
The tie count that triggers the deeming rule comes from five factors: a family tie (UK-resident spouse/partner or child), an accommodation tie (a UK place to live available 91+ continuous days, with at least one night spent there — 16 nights if it's a close relative's home), a work tie (40+ days working more than 3 hours in the UK), a 90-day tie (90+ midnight days in either of the prior two tax years), and a country tie (spending the majority of your midnights in the UK, relevant only if you were resident in any of the prior three years).
Why this isn't your OWR workday count
It's easy to assume the days feeding your residence status and the days feeding your OWR relief are the same number. They aren't. SRT day counting (midnight rule, deeming rule, ties) exists purely to answer "am I UK tax resident this year at all." Your OWR overseas-workday fraction is a separate, later question — once you're established as UK resident, which of your actual workdays involved duties performed outside the UK, used to source how much of your employment income is exempt. A day can be a "UK day" for SRT purposes (you were here at midnight) while the work you did that day was performed entirely overseas, or vice versa around travel days — the two counts simply answer different questions.
Where FIG Tracker fits in
FIG Tracker tracks the workday side of this — overseas versus UK workdays for OWR sourcing, with weekends and GOV.UK bank holidays applied automatically — rather than the SRT residence-day count, which is a separate determination you'd typically confirm with an advisor before using the calculator at all. For how the day-by-day workday classification feeds RSU and bonus sourcing specifically, see how OWR is actually calculated.
FIG Tracker is a calculation aid, not tax advice. Always verify your residence status and figures with a qualified tax advisor before filing with HMRC.