Am I a US tax resident? (Substantial Presence Test)
Spending a lot of time in the US on a visa or as a visitor? The IRS Substantial Presence Test can make you a US tax resident — taxed on your worldwide income — based on a weighted count of your days: all of this year, 1/3 of last year, 1/6 of the year before. Enter your days and see if you cross the line, and whether the closer-connection exception can save you.
Your days in the US
The breakdown
Worked examples
Monterrey consultant with regular US trips — just under the line
Weighted days (toward 183): 178.5 / 183
Your weighted count is 178.5 (118 this year + 40.7 (⅓ of 122) + 19.8 (⅙ of 119)), and you were in the US 118 days this year.
✓ You don't meet it — your weighted total is under 183 (4.5 short).
The breakdown
- This year (2026) — counts ×1: 118 days
- Last year (2025) — counts ×1/3: 40.7 days (of 122)
- Two years ago (2024) — counts ×1/6: 19.8 days (of 119)
- Weighted total: 178.5 days
- 31-day current-year minimum: met (118)
- 183-day threshold: not met
- Result: Not a US tax resident under the SPT this year
Canadian snowbird crosses 183 weighted days, becomes US resident
You meet the Substantial Presence Test: US tax resident
Your weighted count is 208.3 (142 this year + 45 (⅓ of 135) + 21.3 (⅙ of 128)), and you were in the US 142 days this year.
⚠ You meet the test — you'd be treated as a US resident alien, taxed on your worldwide income. See the closer-connection and treaty notes below before concluding.
↩ Possible relief: you were in the US fewer than 183 days this year, so if you kept a tax home abroad all year and have a closer connection to that country, the closer-connection exception (Form 8840) may let you be treated as a nonresident.
The breakdown
- This year (2026) — counts ×1: 142 days
- Last year (2025) — counts ×1/3: 45 days (of 135)
- Two years ago (2024) — counts ×1/6: 21.3 days (of 128)
- Weighted total: 208.3 days
- 31-day current-year minimum: met (142)
- 183-day threshold: met
- Result: US tax resident (worldwide income)
F-1 student living in the US full-time — exempt individual
Your days may be exempt: File 8843
As an exempt individual, your US days generally do not count toward the Substantial Presence Test — students are usually exempt for their first 5 calendar years. You are typically not a US tax resident under this test, but you must still file Form 8843 each year to claim the exemption.
✓ Likely a nonresident under the SPT (exempt individual) — file Form 8843. Check you're within the time limit.
The breakdown
- Your status: Exempt individual (student F/J/M/Q)
- Days counted toward the test: 0 (exempt) — while within the time limit
- Required filing: Form 8843, every year
- Note: Once the exemption period ends, your days start counting.
Examples are recomputed whenever the underlying rates or data change; the date above is the last recompute.
How the test works & data sources
You meet the IRS Substantial Presence Test — and are a US resident alien for tax purposes — if you were physically present in the US on at least 31 days during the current year AND 183 days over three years, counting all the days this year, 1/3 of the days last year, and 1/6 of the days two years ago. Any part of a day in the US counts as a full day. Some days don't count: a regular commuter from Mexico or Canada, days in transit (under 24 hours) between two foreign points, days as a crew member of a foreign vessel, days you couldn't leave for a medical condition that arose in the US, and days as an exempt individual — students (F/J/M/Q, generally for 5 years) and teachers/trainees (J/Q, generally 2 of the last 6 years), who file Form 8843. Even if you meet the test, the closer-connection exception can treat you as a nonresident if you were present fewer than 183 days this year, kept a tax home abroad all year, and have a closer connection to that country — claimed on Form 8840. Meeting the test means your worldwide income is US-taxable unless a tax treaty tie-breaker applies. Green-card holders are US tax residents regardless of days.
Sources: IRS — Substantial Presence Test · IRS — Closer Connection Exception · IRS — Publication 519 (Tax Guide for Aliens)
Frequently asked questions
Does any part of a day count?
Yes. If you were physically in the US at any time on a given day, that's a full day of presence — including your arrival and departure days.
I'm a student on an F-1 visa. Am I a resident?
Usually not for your first 5 calendar years — as an exempt individual your days don't count toward the test. You still file Form 8843 each year to claim the exemption.
I meet the test but I live abroad most of the year. Any relief?
Possibly. If you were in the US fewer than 183 days this year, keep a tax home abroad, and have a closer connection to that country, the closer-connection exception (Form 8840) can treat you as a nonresident. A tax treaty may also help.
What if I meet the test?
You're taxed like a US resident — on your worldwide income — for the part of the year you're a resident. This is a day-count estimate; the residency start/end dates and treaty questions need a cross-border tax professional.