Tax residence is domestic-law driven. Different jurisdictions use different tax years, thresholds, counting methods and tie-break concepts. The operational challenge is to maintain one reliable travel record that can support several adviser reviews.
Why global day counting is messy
The UK focuses heavily on midnights and ties. The US substantial presence test uses a weighted three-year formula. Singapore, Australia, Hong Kong, New Zealand and UAE planning often involve their own day-count or residence indicators. Schengen tracking adds a separate immigration clock that is not the same as tax residence.
For a globally mobile family, the same journey may matter differently in each context. A one-size-fits-all spreadsheet often hides those differences.
What a reliable record needs
- Confirmed entry and exit facts for each journey.
- Tax-year and calendar-year views where relevant.
- Jurisdiction-specific counting assumptions.
- Source quality: manual entry, ticket, boarding pass, receipt, GPS check or adviser note.
- Separate profiles for each family member or client.
How Atrium reduces the burden
Atrium gives the user one place to maintain the travel facts and evidence. The same factual record can then feed UK SRT awareness, CRS self-certification support, adviser exports and future jurisdiction modules without asking the client to rebuild their history each time.
Useful search intents
global tax residency calculator, residence day count app, US substantial presence test, Singapore tax residency, cross-border tax residency evidence.