How the Statutory Residence Test is structured
The SRT, introduced by Schedule 45 of the Finance Act 2013, replaced decades of case law with a structured test applied in a fixed order:
- Automatic overseas tests. Meet any one and you are not UK resident. These are checked first and override everything else.
- Automatic UK tests. If no overseas test is met, meeting any one of these makes you UK resident.
- Sufficient ties test. If neither set decides it, you compare your number of UK ties against your day count using a band table.
Two rules that break most manual counts
The tax year runs 6 April to 5 April. Not January to December. The 2024/25 tax year began on 6 April 2024 and ended on 5 April 2025. Every day from 1 January to 5 April belongs to the tax year that started the previous April — a quarter of the calendar sits in a different year than instinct suggests.
Days are counted at midnight. You spent a day in the UK if you were here at the end of it. So the day you arrive counts, and the day you leave does not:
This is the reverse of the Schengen convention, where both the entry and exit day count in full. If you use a Schengen-style count for the UK you will overstate your total by one day for every separate trip — which, near the 16, 46, 90, 120 or 183-day thresholds, is enough to change the answer.
The sufficient ties bands
Two people with identical day counts can get opposite answers depending on their recent history. A leaver was UK resident in one or more of the three previous tax years; an arriver was not.
| UK days | Leaver needs | Arriver needs |
|---|---|---|
| Fewer than 16 | Automatically non-resident | Automatically non-resident |
| 16 to 45 | 4 ties | Automatically non-resident |
| 46 to 90 | 3 ties | 4 ties |
| 91 to 120 | 2 ties | 3 ties |
| 121 or more | 1 tie | 2 ties |
| 183 or more | Automatically UK resident | |
The asymmetry is deliberate. Someone recently resident is treated as retaining a connection to the UK, and it takes less to pull them back into residence.
A worked example
Suppose you made three trips in 2024/25: 10 April to 10 May, 1 September to 1 October, and 5 January to 4 February. Under the midnight rule each is 30 days, so your total is 90 UK days.
You have a UK family tie, an accommodation tie and a work tie — three ties. If you were UK resident in any of the previous three years you are a leaver, the 46 to 90 band requires 3 ties, and you have exactly 3: UK resident. If you were not resident in any of those years you are an arriver, the same band requires 4 ties, and 3 is not enough: not UK resident. Identical travel, opposite outcomes.
Where this test is genuinely ambiguous
Being straight about the limits matters more here than on any other page in this hub, because the confident-sounding parts of the SRT are surrounded by parts that are not:
- The accommodation tie turns on what counts as "available" to you for 91 continuous days. Gaps of fewer than 16 days are ignored, and a relative's home has a different threshold. Reasonable people disagree.
- Full-time work abroad or in the UK is defined by a "sufficient hours" calculation across a reference period, with rules for gaps, leave and significant breaks. It is not a yes/no question you can eyeball.
- The UK home test requires assessing every home you have in and outside the UK across overlapping periods. It is the most involved of the automatic tests.
- Exceptional circumstances can disregard up to 60 days, but HMRC reads "beyond your control" narrowly, and litigation has generally favoured HMRC.
- The deeming rule can add days you were not present at midnight if you have 3+ ties, were recently resident, and exceed 30 qualifying days.
This calculator takes the ambiguous items as your declarations rather than pretending to resolve them. If your position depends on one of them, that is exactly the point at which to involve an adviser.
Keeping records HMRC will accept
The SRT puts the burden of proof on you. If your position is that you were non-resident, you need to be able to evidence your day count years later, and "I think I was there about four months" is not evidence.
What actually holds up: boarding passes and e-tickets, passport stamps where they exist, bank and card transactions showing where you were spending, mobile phone records, and a contemporaneous travel log kept as you go rather than reconstructed afterwards. HMRC has challenged day counts successfully where records were thin, and the taxpayer bears the cost of the doubt.
Two practical points. Keep the record for at least six years, since that is how far back a discovery assessment can normally reach. And note the days you were in the UK and why — because if you ever need to argue exceptional circumstances, you will need to show the reason was genuinely beyond your control at the time, not reconstructed to fit.
Related counting rules
The UK's rules are unusual in using a tax year that is not the calendar year and a midnight-based day count. If you are tracking other countries at the same time, the tax residency day tracker applies each country's own threshold to one shared trip log, and the US Substantial Presence Test uses a weighted three-year formula that works differently again.