Rule type

Substantial Presence Test

The Substantial Presence Test is a 3-year weighted day-count formula used by the US to determine tax residency for non-citizens. Current-year days at full weight, prior-year at 1/3, two-years-prior at 1/6.

1 jurisdictions use this rule.

How Substantial Presence Test works

The Substantial Presence Test is unique to the United States. Rather than a single 183-day threshold, it weights three years: current year × 1, prior year × 1/3, two years prior × 1/6. You meet the SPT if both: (1) you spent at least 31 days in the US in the current year, and (2) the weighted total is 183 or more. Meeting the SPT triggers worldwide income taxation, unless you qualify for the closer-connection exception or apply a treaty tie-breaker.

Notable examples

  • 120 days each year for 3 years = 120 + 40 + 20 = 180 weighted days. Under 183, no SPT.
  • 150 days current + 120 prior + 120 two-years-prior = 150 + 40 + 20 = 210. SPT met.
  • Closer-connection exception (Form 8840) preserves non-resident status if current-year days < 183.

Jurisdictions using Substantial Presence Test

1 jurisdictions. Search, filter, and click through to per-jurisdiction details.

Showing 1 of 1 jurisdictions

Jurisdiction CodeRule type Threshold Period
United States (Federal)USSubstantial Presence183 daysCalendar year (Jan 1 – Dec 31)

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