Substantial Presence Test calculator
The IRS Substantial Presence Test (SPT) decides whether non-citizens are US tax residents. It's a 3-year weighted formula — easy to misapply, expensive to miss. Plug your numbers in and see your status.
Days in the United States
Count any day on which you were physically present in the US, with limited exceptions (transit days, exempt-individual days, medical days). Partial days count as full days.
- 2026: 0 × 1 = 0.00
- 2025: 0 × 1/3 = 0.00
- 2024: 0 × 1/6 = 0.00
The SPT formula
You meet the Substantial Presence Test if both are true:
- You were physically present in the US for at least 31 days in the current year, AND
- Your weighted total is 183 days or more:
current + 1/3 × prior + 1/6 × two-years-prior
Exempt individuals
Some categories of people exclude their US days entirely: foreign government-related individuals (A or G visa), teachers and trainees on J or Q visa (limited), students on F, J, M, or Q visa (limited to 5 calendar years), and a few others. If you're an exempt individual, this calculator's inputs should reflect only non-exempt days.
The closer-connection exception
Even if you meet the SPT, you can still be treated as a non-resident if all of these are true: your current-year US days are under 183, you maintain a tax home in a foreign country, and you have a closer connection to that country. File Form 8840 to claim the exception.
Read the full guides: The Substantial Presence Test calculated step-by-step and The closer-connection exception (Form 8840) explained.
Track the SPT in real time on your iPhone
Tax Days runs the full 3-year weighted SPT calculation as you log trips. Notifications fire 30, 14, 7, 3, and 1 days before you'd cross 183 weighted days.
