Free tool
US Substantial Presence Test Calculator
Moving to or spending time in the US? Enter your days over three years and see whether you meet the Substantial Presence Test that makes you a US tax resident, taxed on your worldwide income.
How many days were you physically present in the US in each year?
Counts in full. Any part of a day in the US usually counts as a day.
Counts as one third.
Counts as one sixth.
The test: at least 31 days this year, and a weighted three-year total of at least 183 days. Indicative only. A green card makes you a US resident regardless of days, and some days (for certain visas) are exempt.
Substantial Presence Test
Enter your US days
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How the Substantial Presence Test works
The US decides tax residence differently from the UK. If you are not a US citizen and do not hold a green card, you become a US tax resident for a calendar year when you are present for at least 31 days in that year and your weighted three-year day count reaches 183. The weighting counts every day this year, a third of last year's days, and a sixth of the days from the year before that.
Meeting the count is not always the end of the story. If you were in the US for fewer than 183 days this year, you may claim the closer-connection exception, and a UK resident can often rely on the UK-US treaty tie-breaker, but both must be claimed properly. Because the US taxes residents on worldwide income and brings your UK accounts into US reporting, the arrival year is where the planning matters most. This tool gives an indication only.
Getting the two sides right
Being resident in both countries at once, or in neither cleanly, is where cross-border tax goes wrong. We handle your UK position and the treaty side, and our US partners (an Enrolled Agent or CPA) handle the US return, on a fixed fee agreed upfront. Book a free clarity call.