How the calculator counts
- Enter totals or add trips. Any part of a day in the US counts, arrival and departure days included, in the calendar year you pick and the two before it.
- The weighting is shown row by row. This year counts in full, last year at a third and the year before at a sixth, so you can check the total yourself.
- Each condition has its own tracker. Days this year against 31, and the weighted total against 183. You're resident only once both are reached.
- Some cases aren't modelled. A green card makes you resident whatever your days, and the closer connection exception can keep you nonresident. Leave out exempt days, and file Form 8843 where it's needed.
The Substantial Presence Test
You're a US resident for tax purposes if you spend at least 31 days in the US this year and 183 weighted days across three years — this year in full, last year at 1/3, the year before at 1/6. A green card makes you resident whatever your days, and the closer connection exception can keep you nonresident under 183 days this year.
Living abroad as a US taxpayer
US citizens and green card holders are taxed on worldwide income wherever they live. Working abroad, you can exclude foreign earned income up to an annual cap if you spend 330 full days outside the US in any 12 months.