US Substantial Presence Test calculator
Count all current-year days, one-third of last year’s days and one-sixth of the year before. Then check exclusions and exceptions before relying on the result.
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How the weighted total works
The day test requires at least 31 days in the current year and a weighted three-year total of at least 183 days. The current year counts in full, the previous year at one-third and the second previous year at one-sixth.
What this result cannot decide
- Whether days qualify for an exempt-individual or medical-condition exclusion
- Whether a closer-connection exception or treaty applies
- Your official residency starting or ending date
Track every trip from one ledger
The shared local tracker reuses the same recorded dates across US, UK, Schengen and country threshold views.
Frequently asked questions
How do you calculate the substantial presence test?
First check for at least 31 US days in the current year. Then add all countable current-year days, one-third of the previous year’s countable days and one-sixth of the second previous year’s countable days. The basic day test is met when both gates are satisfied, subject to exclusions and exceptions.
How do you calculate the 183-day rule?
For this US test, 183 is a weighted three-year total, not simply 183 physical days in the current year. Current-year days count in full, the prior year at one-third and the second prior year at one-sixth.
How can someone meet the substantial presence test?
The basic day-count test requires at least 31 countable US days in the current year and at least 183 weighted days across the three-year formula. Exempt days, medical exclusions, closer-connection rules and treaties can change the final treatment.
Who may be treated as an exempt individual for day counting?
Depending on detailed IRS conditions and time limits, some foreign-government-related individuals, certain teachers or trainees, certain students and professional athletes temporarily present for a charitable sports event may exclude days. Review the IRS instructions and Form 8843; the calculator does not decide eligibility.