What counts as a 'day' present in the US under the SPT?

Generally, any day you are physically present in the US for any part of the day counts as a full day. Exceptions exist for transit between two foreign points (less than 24 hours in the US), commuter days from Canada or Mexico, medical conditions that arose while in the US, and days as an exempt individual (like students or scholars).

Substantial Presence Test Calculator

Q: Does a green card override the Substantial Presence Test?

Yes. If you hold a green card (lawful permanent residence status) at any time during the calendar year, you are automatically classified as a US tax resident. The Substantial Presence Test is only used for non-citizens who do not hold a green card.

Determine your US tax residency status instantly. Enter your physical days in the US for the last three years to calculate your weighted total. No signup required.

Green Card Holders: If you hold a US Green Card (lawful permanent resident status) at any time during the year, you are automatically classified as a US tax resident under the Green Card Test, regardless of the number of days you spend in the country. The Substantial Presence Test is not applicable to you.

Enter US Presence Days

Weighted Results

Actual Days (This Year) 0

Weighted Total Days 0 / 183

Weighted Day Count Progress 0%

0 days

You do not meet the Substantial Presence Test. You are classified as a Nonresident Alien for US tax purposes.

Disclaimer: This calculator is for informational purposes only and does not constitute immigration or tax advice. US federal tax rules are complex and vary by individual circumstances. Consult a qualified CPA or tax attorney for guidance specific to your situation.

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Understanding the US Substantial Presence Test (SPT)

The United States uses the Substantial Presence Test (SPT) to determine whether non-US citizens (who do not hold Green Cards) are considered resident aliens for federal income tax purposes.

1. The Weighted Day Count Formula

The Substantial Presence Test is not a simple calculation of spending 183 days in a single year. Instead, it utilizes a weighted day-count formula looking at your presence over a three-year period.

To meet the test, you must be physically present in the United States for at least 31 days during the current calendar year, and the sum of your weighted days over the three-year period must equal at least 183 days.

The formula is calculated as follows:

Weighted Days Formula:


            Weighted Days = (Days in Current Year × 1) + (Days in Last Year × 1/3) + (Days in Two Years Prior × 1/6)

Worked Example:

Suppose you spend time in the US as follows:

Current Year: 120 days
Last Year: 120 days (weighted: 120 × 1/3 = 40 days)
Two Years Prior: 120 days (weighted: 120 × 1/6 = 20 days)

Your total weighted days would be: 120 + 40 + 20 = 180 days. Since 180 is less than 183, you do not meet the test (assuming you do not hold a Green Card). However, if you spent just 3 more days in the current year, you would reach 183 days and meet the test.

2. Who Does the Substantial Presence Test Apply To?

The SPT applies to non-US citizens who are not lawful permanent residents (Green Card holders).

US Citizens and Green Card Holders: Are automatically classified as US tax residents and are subject to US taxation on their worldwide income, regardless of physical presence. The SPT is not used for these individuals.
Nonresident Aliens: Non-citizens who do not meet the SPT are taxed only on their US-source income (and not on their worldwide income).
Federal vs. State Residency: The SPT is a federal tax test. Individual states (like California, New York, or Florida) have entirely separate rules for state income tax residency. It is common to be classified as a US resident at the federal level while remaining a nonresident at the state level, or vice versa.

3. The Closer Connection Exception (Form 8840)

Even if your weighted day count equals or exceeds 183 days, you may still be treated as a nonresident alien if you qualify for the Closer Connection Exception.

To qualify for the Closer Connection Exception under IRS rules, you must meet the following:

You are physically present in the US for fewer than 183 days during the current calendar year.
You maintain a tax home in a foreign country.
You establish that you have a closer connection to that foreign country than to the US (evaluated based on housing, family, vehicle registration, driver's licenses, and social ties).
You file IRS Form 8840 (Closer Connection Exception Statement for Aliens) by the annual filing deadline.

4. Consequences of Meeting the Substantial Presence Test

Meeting the SPT changes your tax status from a Nonresident Alien to a Resident Alien. This triggers major tax compliance obligations:

Worldwide Income: You must report and pay US income tax on your worldwide income from all sources inside and outside the US.
FBAR & FATCA Disclosure: You are subject to foreign asset reporting requirements, including filing FinCEN Form 114 (FBAR) if the aggregate value of your foreign financial accounts exceeds $10,000 at any point during the year, and Form 8938 (FATCA) for specified foreign financial assets.
Tax Forms: You must file IRS Form 1040 (standard resident return) instead of Form 1040-NR (nonresident return).

5. The First-Year Choice Election

If you do not meet the SPT in your year of arrival but expect to meet it in the following year, you may elect to be treated as a US resident alien for a portion of the arrival year. This is known as the "First-Year Choice". Specific rules require you to be present in the US for at least 31 consecutive days and meet other criteria to qualify.

Substantial Presence Test FAQs

Yes. If you hold a Green Card (lawful permanent resident status) at any time during the year, you are automatically classified as a US tax resident. The Substantial Presence Test is only used for non-citizens who do not hold a Green Card.

Generally, any calendar day you spend in the US, even for a few minutes, counts as a full day. Exceptions exist for:

Transit days where you pass through the US between two foreign points (for less than 24 hours).
Commuter days for residents of Canada or Mexico who regularly commute to work in the US.
Days you were unable to leave the US due to a medical condition that arose while in the US.
Days you are considered an "exempt individual" (like students or scholars).

Yes. The Substantial Presence Test is a federal test. Individual states (like California, New York, or Florida) have their own independent statutory residency and domicile tests. Meeting the federal SPT makes you a US tax resident, but does not automatically make you a state tax resident, and vice versa.

If you are present in the US for fewer than 183 days in the current year, but your weighted total over 3 years is 183 or more, you can avoid US tax residency by filing Form 8840 to establish that you have a closer connection to a foreign country where you maintain a tax home.

Students on F, J, M, or Q visas, and teachers/trainees on J or Q visas, are classified as "exempt individuals" for a certain period of time. Days spent in the US under these exempt statuses do not count toward the Substantial Presence Test (typically up to 5 years for students, and 2 years for teachers). You must file Form 8843 annually to claim this exemption.

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