How are days counted for the automatic UK overseas tests and automatic UK tests in 2025?
Executive summary
HMRC’s Statutory Residence Test (SRT) counts a “day in the UK” mainly by presence at midnight; automatic overseas tests can declare you non‑resident if you spend fewer than specified day thresholds (eg. fewer than 16 days if you were UK resident in one or more of the previous three tax years), while automatic UK tests include spending 183 days or more in the tax year or having a UK home under specified conditions [1] [2] [3]. The government guidance and commentary also explain a “deeming” rule that can convert qualifying days into counted days after the first 30 qualifying days in the tax year [4].
1. How the SRT defines “a day spent in the UK” — midnight is the marker
For the purposes of counting days under both the automatic overseas and automatic UK tests, the key practical rule is whether you were physically present in the UK at midnight on a given day: if you were, that day normally counts as a day spent in the UK [1] [5]. Advisory and practitioner write‑ups repeat the same operational test — presence at the end of the day (midnight) is the trigger for inclusion [5].
2. Automatic overseas tests — thresholds for being non‑resident
The automatic overseas tests are the first step; they can make you non‑resident if you meet one of the tests. A commonly cited example: if you were resident in the UK in one or more of the previous three tax years, you will be non‑resident in the current tax year if you spend fewer than 16 days in the UK that tax year [1] [2]. Other automatic overseas tests relate to working full‑time abroad and the pattern of days/hours worked overseas — those require careful record keeping of days and overseas hours [2] [6].
3. Automatic UK tests — thresholds that make you resident
The automatic UK tests operate the other way: if you meet one, you are UK resident. The most straightforward is spending 183 days or more in the tax year [3]. Other automatic UK tests include having a UK home where you are present for specified minimum periods (eg. a 91‑day home existence with at least 30 days’ presence within the tax year) or working in the UK on a “full‑time” basis [1] [7].
4. The deeming rule — qualifying days can be “converted” into counted days
HMRC’s internal guidance explains the deeming rule: if you meet its conditions, after the first 30 qualifying days all subsequent qualifying days in the tax year are treated as days spent in the UK and must be aggregated into your day count [4]. Practitioners and explanatory guides restate this: once the deeming rule applies, you must total days present at midnight plus qualifying days beyond the 30‑day threshold [8] [4].
5. Practical implications — records, split years and edge cases
Because the tests hinge on small numeric thresholds (16, 46, 90, 183 days in different scenarios) and on presence at midnight, advisers and firms stress keeping detailed arrival/departure records and work‑hour logs if you rely on overseas working tests [2] [9]. Split‑year treatment and other technical rules can affect how parts of a year are treated for residence, so professional advice is commonly recommended for borderline situations [10] [9].
6. Areas where sources differ or leave gaps — what reporters and readers should note
The materials provided are consistent on the core rules (midnight presence; thresholds such as 16 and 183 days; the deeming rule) but differ in emphasis: HMRC internal guidance focuses on technical application and the deeming mechanism [4], while law‑firm and accountancy summaries emphasise tax planning, split‑year treatment and new regime consequences from April 2025 [1] [9]. Available sources do not mention every specific threshold for every circumstance (for example, precise day limits under all permutations of the automatic overseas/automatic UK/ ties tables) — readers should consult primary HMRC SRT tables or professional advisers for a full checklist (not found in current reporting).
7. What readers should do next — verification and professional advice
If your residency hinges on a handful of days, verify each night’s presence against the midnight rule and check whether the deeming rule could enlarge your counted days [5] [4]. For people working overseas, keep detailed logs of net overseas hours and breaks to satisfy the overseas‑work tests [2] [6]. For definitive application to your tax year, consult the official HMRC SRT guidance and, where needed, a tax adviser — practitioner guides warning of split‑year complications and IHT/residence reforms underscore the stakes [10] [9].
Limitations: this analysis uses only the documents provided and therefore summarises the commonly‑cited mechanics (midnight presence, key numeric thresholds, and the deeming rule) but does not reproduce the SRT’s full tables or every special case; for specific calculations use HMRC’s published SRT tables and, if necessary, professional advice (not found in current reporting).