Who it applies to
People checking the US substantial presence test who are not relying solely on citizenship or a green card to establish US tax status.
US tax — substantial presence
The substantial presence test adds all qualifying days in the current calendar year, 1/3 of qualifying days in the previous calendar year, and 1/6 of qualifying days two calendar years earlier. At least 31 current-year days and 183 weighted days are required. Check exempt days and any applicable exceptions before interpreting the total.
Check your own dates: US tax — substantial presence calculator →
Summary
- Day rule / reminder
- 183 weighted days over 3 years · at least 31 this year
- Window
- Current year and the previous two years
- What the tool measures
- The recorded-day component
- Official reference
- IRS substantial presence test ↗
The substantial presence test adds all qualifying days in the current calendar year, 1/3 of qualifying days in the previous calendar year, and 1/6 of qualifying days two calendar years earlier. At least 31 current-year days and 183 weighted days are required. Check exempt days and any applicable exceptions before interpreting the total.
The rule
Excluded days, medical exceptions, the closer-connection exception and treaties can change the result. Exclude dates only when Internal Revenue Service rules allow it; the app does not decide which exceptions you qualify for.
Counting the days
Adds all qualifying days in the current year, one third of the previous year and one sixth of the year before that. Permitted exclusions are applied before these fractions. At least 31 qualifying days in the current year are also required.
- Choose the date through which you want to count, then add your recorded visits.
- Use the counting convention above. Overlapping recorded dates in the relevant region are counted only once.
- Read the result alongside the conditions. Missing records and other eligibility requirements are not inferred from a total.
Examples
These examples demonstrate the counter's arithmetic, using a count-through date of 30 October 2026. They do not determine legal status or eligibility.
Example 1 — one recorded visit
- to · United States
Recorded result: 10 weighted days
Example 2 — overlapping records
- to · United States
- to · United States
Recorded result: 15 weighted days
Example 3 — two visits with a gap
- to · United States
- to · United States
Recorded result: 16 weighted days
Exceptions & edge cases
Excluded days, medical exceptions, the closer-connection exception and treaties can change the result. Exclude dates only when Internal Revenue Service rules allow it; the app does not decide which exceptions you qualify for.
Use the official reference for the full conditions and any changes since the source review date shown on this page.
Common misconceptions
“A count below the day threshold settles tax residence.”
A recorded-day total is one component. Review the separate conditions and exceptions described on this page.
“Unrecorded days are included in the total.”
The calculator uses only the dates you enter. Missing history can make the result incomplete.
Frequently asked questions
What does this rule count?
The substantial presence test adds all qualifying days in the current calendar year, 1/3 of qualifying days in the previous calendar year, and 1/6 of qualifying days two calendar years earlier. At least 31 current-year days and 183 weighted days are required. Check exempt days and any applicable exceptions before interpreting the total.
Which counting window does this tool use?
Current year and the previous two years. Adds all qualifying days in the current year, one third of the previous year and one sixth of the year before that. Permitted exclusions are applied before these fractions. At least 31 qualifying days in the current year are also required.
What else should I check before relying on the total?
Excluded days, medical exceptions, the closer-connection exception and treaties can change the result. Exclude dates only when Internal Revenue Service rules allow it; the app does not decide which exceptions you qualify for.
Where can I read the official requirements?
Read IRS substantial presence test ↗. The source was last reviewed on .
Keep this count with your travel history.
Follow your recorded days and selected reminders in Untild, alongside your other travel counters.
Get Untild for iPhone ↗Sources
Source last reviewed: . This is the source review date, not a claim that every legal condition is calculated.
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