What is Substantial Presence Test?

Definition

The Substantial Presence Test (SPT) is the primary method the IRS uses to determine whether a foreign national qualifies as a US resident for tax purposes. Meeting this test means the individual is taxed on worldwide income by the US, just like a US citizen. The test is found in IRC Section 7701(b) and uses a mechanical day-counting formula — no subjective factors like intent or domicile are considered. The 183-Day Formula: You meet the Substantial Presence Test for the current calendar year if two conditions are satisfied. First, you were physically present in the US for at least 31 days during the current year. Second, the sum of the following equals 183 days or more: all days present in the US during the current year, plus one-third of the days present in the prior year, plus one-sixth of the days present in the year before that. For example, if a Canadian snowbird spent 120 days in the US in each of the past three years: 120 (current) + 40 (120 x 1/3) + 20 (120 x 1/6) = 180 days — just below the threshold. But 122 days each year would trigger it: 122 + 40.67 + 20.33 = 183. What Counts as a 'Day': Any part of a day in the US counts as a full day for the Substantial Presence Test (unlike the Physical Presence Test for the FEIE, which requires full 24-hour days). This means arriving at 11:00 PM on a flight from Toronto counts as a full day. Days in transit through the US count. However, certain categories of days are excluded: days you could not leave the US due to a medical condition that arose while in the US, days spent commuting to work from Canada or Mexico (within a specified corridor), and days spent in transit between two foreign points with a US connection lasting less than 24 hours. Exempt Individuals: Certain categories of foreign nationals are exempt from counting days toward the SPT. Students on F, J, M, or Q visas are generally exempt for their first five calendar years. Teachers and researchers on J or Q visas are exempt for their first two calendar years. Foreign government-related individuals and diplomats with A or G visas are exempt. Professional athletes temporarily in the US for charitable sports events are exempt. These exemptions mean the individual's days in the US are simply not counted in the formula. Closer Connection Exception: Even if you meet the 183-day formula, you can avoid US tax residency if you were present in the US fewer than 183 days during the current year AND you maintained a 'closer connection' to a foreign country (meaning your tax home and significant personal and economic ties are in that country). You must file Form 8840 (Closer Connection Exception Statement) by the tax return due date to claim this exception. For Canadian snowbirds, maintaining a Canadian tax home, driver's license, health insurance, bank accounts, and social ties all support a closer connection claim. Treaty Tie-Breaker Rules: If you meet the Substantial Presence Test and cannot use the Closer Connection Exception, you may still avoid US tax residency by invoking the tie-breaker provisions of an applicable tax treaty. Under the US-Canada Tax Treaty (Article IV), tie-breaker criteria are applied in order: permanent home, center of vital interests, habitual abode, and nationality. If these rules determine you are a Canadian resident, you can be treated as a nonresident alien for US tax purposes. You must file Form 8833 to disclose the treaty-based position and still file Form 1040-NR as a nonresident. Consequences of Meeting the Test: If you meet the SPT and no exception or treaty override applies, you become a US tax resident. This means filing Form 1040, reporting worldwide income (including Canadian income), potentially claiming Foreign Tax Credits, and complying with FBAR and FATCA reporting requirements for all foreign financial accounts. For Canadian residents who inadvertently meet the test, the compliance burden and potential double taxation can be severe. Critical Planning for Canadian Snowbirds: Canadians spending winters in the US must count their days carefully using the weighted formula. A common safe harbor is limiting US presence to no more than 120 days per year, which under the formula produces: 120 + 40 + 20 = 180 days — safely below 183. Even so, filing Form 8840 annually as a protective measure is strongly recommended. Days at a US vacation property, visiting family, attending medical appointments, or shopping trips all count.

Related Forms

Common Mistakes to Avoid

• 1Assuming you must be present 183 days in a single year to trigger the test — the weighted formula counts days across three years, so 120 days per year can be enough
• 2Forgetting to file Form 8840 for the Closer Connection Exception, which must be filed proactively even if you believe you are clearly a Canadian resident
• 3Not counting partial US days (arriving at 11 PM on a flight still counts as a full day for SPT purposes)

Related Terms