UK Statutory Residence Test. A day counts if you are in the UK at midnight at the end of it
(
RFIG20710);
tax year is 6 Apr – 5 Apr. Day bands and tie counts per
RDR3 /
RFIG20520
(verified 11 Jun 2026). Not modelled: automatic home / full-time-work tests, the deeming rule, transit days,
exceptional circumstances, split-year treatment. Crown dependencies (incl. Guernsey) correctly do
not count as UK.
US Substantial Presence Test
(
IRS, verified 24 Jun 2026):
resident if present ≥ 31 days this
calendar year and the weighted total
(this year + ⅓ of last year + ⅙ of the year before) ≥ 183. A day counts if you are in the US at
any time
(not just midnight). Not modelled: the <24h transit exemption, exempt-individual status (F/J/M/Q visas),
the closer-connection exception, and treaty tie-breakers. US airspace doesn't count, so overflights are excluded.
Guernsey residence (
gov.gg, Income Tax (Guernsey) Law 1975 s.3, verified 24 Jun 2026),
on a
calendar year.
Resident: 91+ days, or 35+ days and 365+ over the previous 4 years.
Principally resident: 182+ days, or 91+ days and 730+ over the previous 4 years.
Solely resident: resident and not resident (91+ days) anywhere else. Day counting here is any-part-of-day
presence; the permanent-move limb of principal residence and the precise statutory day definition are not modelled.
The "not resident elsewhere" test for sole residence is approximated as <91
midnights in any other single
country (a coarser, different basis than the any-part-of-day count used for Guernsey itself), and earlier years are
under-counted where they predate GPS tracking.
Presence is inferred from phone GPS — audit amber/hatched days. This is an estimate, not tax advice.