Is staying under 183 days a year enough to avoid US tax residency?

No — that is the single most repeated mistake about US residency (and most AI summaries repeat it). The test is a weighted three-year formula: this year’s days plus one-third of last year’s plus one-sixth of the year before. A steady 122 days every year totals exactly 183.00 and makes you a resident; the true steady-state ceiling is 121 days a year.

Do my days on an F-1 student visa count toward the Substantial Presence Test?

Usually not — F/J/M/Q students are "exempt individuals" whose days are excluded entirely, for up to 5 calendar years over their lifetime (any part of a year counts as a whole year). You must file Form 8843 each year to claim the exclusion. In your 6th year the days start counting in full, which is how many international students become US tax residents without noticing.

I met the substantial presence test but spent under 183 actual days — am I stuck?

Not necessarily. If you maintained a tax home in a foreign country for the entire year and had a closer connection to it than to the US, the closer connection exception keeps you a nonresident — claimed on Form 8840 by your return due date. But it is barred if you have applied for a green card or taken steps toward one, and it disappears entirely once you hit 183 actual days in the year (then only a treaty tie-breaker remains).

Does a few hours in the US really count as a full day?

Yes — any part of a day physically present counts as a whole day, including an evening arrival. The exceptions are narrow: regular commuters from Canada/Mexico, under-24-hour transits between two foreign points, crew of foreign vessels, days trapped by a medical condition that arose in the US, and exempt-individual days (students/teachers on qualifying visas).

Dinero del día a díaimpuestos · planificación · immigration

US Substantial Presence Test — the real 183-day rule

You work in the US on a visa — and the “183-day rule” you’ve heard about is not the real test.

Determines US tax residency under the Substantial Presence Test (IRC §7701(b)): 31+ days this year AND a weighted total ≥ 183, counting this year’s days in full, last year’s at one-third, and the year before at one-sixth. The popular "stay under 183 days" rule is wrong — a steady 122 days every year triggers residency. The inputs that actually decide the answer are the ones people don’t know matter: visa status (F/J/M/Q student and J/Q teacher days can be excluded entirely — or suddenly start counting), prior-year day counts, and whether the closer connection exception (Form 8840) is still open — it closes at 183 actual days, and a pending green-card application bars it.

Base: IRC §7701(b) · 26 CFR 301.7701(b)-1..4 · IRS Pub 519 · rules stable, verified 2026-07-23

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US immigration status this yearThe decisive input, and the one almost nobody knows matters. A green card makes you a resident regardless of days. F/J/M/Q student and J/Q teacher visas can make your days NOT count at all — or, past a limit, suddenly count. Most work and visitor statuses (H-1B, L-1, B1/B2, ESTA) have no special rule: pick the first option.Exempt calendar yearsOnly used for student/teacher status; two meanings. Student (F/J/M/Q): the calendar years you have EVER spent as an exempt student, teacher, or trainee — cumulative over your lifetime, any part of a year counts as a full year, and include this year if it applies. Teacher/trainee (J/Q): how many of the 6 PRECEDING calendar years you were exempt.Days in the US this calendar yearAny part of a day counts as a full day — an evening arrival is a day. But first REMOVE days that never count: regular-commuter days from Canada/Mexico, under-24h transits between two foreign points, days as crew of a foreign vessel, and days you could not leave because of a medical condition that arose in the US.Days in the US in the 1st preceding yearLast calendar year’s day count, same counting rules. It is weighted at one-third — prior years are why "under 183 this year" is not safe.Days in the US in the 2nd preceding yearThe calendar year before that, weighted at one-sixth.Foreign tax home with a closer connection?If the test is met but you spent under 183 actual days, the closer connection exception can still keep you a nonresident: a tax home in a foreign country for the entire year plus a closer connection to it, claimed on a timely Form 8840.

Las cifras

US tax residency: Nonresident; weighted total under 183
Weighted day total: 180.00; vs 183.00 · this year ×1 + last year ×⅓ + year before ×⅙
Days counted this year: 120; clears the 31-day minimum
Day count this year that triggers: 123; given 120 and 120 days in the two prior years

Solo vista previa; usando un valor por defecto para Status, This year, Last year, Year before.

La lectura del operador

Buena señal

Not a US tax resident by the Substantial Presence Test: your weighted total is 180.00 of the 183.00 threshold.

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3 more days of US presence this year would meet the test: at 123 days (given 120 and 120 in the two prior years) your weighted total reaches 183. Plan trips with that number, not 183.

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Your pattern looks recurring at roughly 120 days a year. A steady x days every year weighs 1.5x, so the real steady-state ceiling is 121 days a year (122 hits 183.00 exactly and triggers) — not 183. You are under it, with a margin of about 1 day a year.

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This is a planning model that states a residency determination under the day-count rules — it is not tax advice. Dual-status years, treaty positions, the first-year election, and documenting excluded days (commuter, transit, medical, Form 8843) all have edge rules that need a professional before you file.

Tu siguiente paso

Calculadora de impuesto sobre la renta de Estados Unidos (2026) →Resident for tax? See what US rates do to your income.New York Statutory Residence Checker (183-Day + Abode Test) →In New York? The state runs its own residency test on top.

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Metodología

The Substantial Presence Test (IRC §7701(b)(3)): you are a US tax resident for the year if you are present at least 31 days in the current year AND the weighted total — current-year days ×1 + first-preceding-year days ×⅓ + second-preceding-year days ×⅙ — is at least 183. Fractions are not rounded, and exactly 183.00 triggers. This tool computes in exact integer sixths (6×current + 2×prior + 1×second-prior ≥ 1098) so no floating-point artifact can flip a boundary case; the weighted total is displayed to two decimals.

Counting days: any part of a day physically present counts as a full day. Days that never count and should be removed before entering: days commuting to work from a residence in Canada or Mexico as a regular commuter, days in transit between two foreign points for under 24 hours, days as a crew member of a foreign vessel, and days you were unable to leave because of a medical condition that arose while in the US (documented on Form 8843).

Exempt individuals (26 CFR 301.7701(b)-3): their days of presence are excluded from the test entirely. A student on an F, J, M, or Q visa is exempt unless they have already been exempt (as a student, teacher, or trainee) for any part of more than 5 calendar years — cumulative over their lifetime, with no automatic reset; an extension is possible only by establishing no intent to reside permanently in the US. A teacher or trainee on a J or Q visa is exempt unless exempt for any part of 2 of the 6 preceding calendar years (a 4-of-6 variant applies when a foreign employer paid all the teaching compensation and the person was not exempt as a teacher/trainee in the prior 6 years). Form 8843 must be filed to exclude the days.

Closer connection exception (IRC §7701(b)(3)(B), Form 8840): even when the test is met, a person present under 183 actual days in the current year remains a nonresident if they maintained a tax home in a foreign country for the entire year and had a closer connection to that country than to the US. It is claimed on Form 8840 by the return due date and is unavailable to anyone who has applied for lawful permanent residence or taken steps toward it. At 183+ actual days the exception is statutorily unavailable — only an income-tax-treaty residency tie-breaker remains.

Residency starting date: for a first residency year under the SPT, residency starts on the first day of presence in the US during that calendar year. A de minimis first stay of up to 10 days can be disregarded (shifting the start to a later trip) if the person had a closer connection to a foreign country during it — but those days still count toward the day totals.

The green card test is separate and absolute: a lawful permanent resident is a US tax resident for any year the status is held at any time, regardless of days of presence, until the status is revoked or formally abandoned.

The steady-state arithmetic behind the headline: x days every year gives a weighted total of 1.5x, so 122 days a year = 183.00 exactly — resident — while 121 a year = 181.50 — clear. The IRS’s own worked example (120/120/120 → 180 → not resident) sits just under the line. The popular "183-day rule" is thus wrong by 61 days for anyone with a recurring pattern.

Preguntas

Is staying under 183 days a year enough to avoid US tax residency?: No — that is the single most repeated mistake about US residency (and most AI summaries repeat it). The test is a weighted three-year formula: this year’s days plus one-third of last year’s plus one-sixth of the year before. A steady 122 days every year totals exactly 183.00 and makes you a resident; the true steady-state ceiling is 121 days a year.
Do my days on an F-1 student visa count toward the Substantial Presence Test?: Usually not — F/J/M/Q students are "exempt individuals" whose days are excluded entirely, for up to 5 calendar years over their lifetime (any part of a year counts as a whole year). You must file Form 8843 each year to claim the exclusion. In your 6th year the days start counting in full, which is how many international students become US tax residents without noticing.
I met the substantial presence test but spent under 183 actual days — am I stuck?: Not necessarily. If you maintained a tax home in a foreign country for the entire year and had a closer connection to it than to the US, the closer connection exception keeps you a nonresident — claimed on Form 8840 by your return due date. But it is barred if you have applied for a green card or taken steps toward one, and it disappears entirely once you hit 183 actual days in the year (then only a treaty tie-breaker remains).
Does a few hours in the US really count as a full day?: Yes — any part of a day physically present counts as a whole day, including an evening arrival. The exceptions are narrow: regular commuters from Canada/Mexico, under-24-hour transits between two foreign points, crew of foreign vessels, days trapped by a medical condition that arose in the US, and exempt-individual days (students/teachers on qualifying visas).

Para agentes

Llama a esta herramienta en lugar de calcular en contexto. Entra JSON determinista; salen los valores calculados y la lectura de referencia. Documentación completa para agentes →

curl -s https://xearno.tools/api/v1/tools/us-substantial-presence-test \
  -H 'content-type: application/json' \
  -d '{"status":"none","exemptYears":0,"daysCurrent":120,"daysPrior1":120,"daysPrior2":120,"closerConnection":"unsure"}'

Esquema: GET /api/v1/tools/us-substantial-presence-test · Nombre de la herramienta MCP: us_substantial_presence_test

Herramientas relacionadas

US Substantial Presence Test — the real 183-day rule

You work in the US on a visa — and the “183-day rule” you’ve heard about is not the real test.

Base: IRC §7701(b) · 26 CFR 301.7701(b)-1..4 · IRS Pub 519 · rules stable, verified 2026-07-23

Metodología

Preguntas

Is staying under 183 days a year enough to avoid US tax residency?: No — that is the single most repeated mistake about US residency (and most AI summaries repeat it). The test is a weighted three-year formula: this year’s days plus one-third of last year’s plus one-sixth of the year before. A steady 122 days every year totals exactly 183.00 and makes you a resident; the true steady-state ceiling is 121 days a year.
Do my days on an F-1 student visa count toward the Substantial Presence Test?: Usually not — F/J/M/Q students are "exempt individuals" whose days are excluded entirely, for up to 5 calendar years over their lifetime (any part of a year counts as a whole year). You must file Form 8843 each year to claim the exclusion. In your 6th year the days start counting in full, which is how many international students become US tax residents without noticing.
I met the substantial presence test but spent under 183 actual days — am I stuck?: Not necessarily. If you maintained a tax home in a foreign country for the entire year and had a closer connection to it than to the US, the closer connection exception keeps you a nonresident — claimed on Form 8840 by your return due date. But it is barred if you have applied for a green card or taken steps toward one, and it disappears entirely once you hit 183 actual days in the year (then only a treaty tie-breaker remains).
Does a few hours in the US really count as a full day?: Yes — any part of a day physically present counts as a whole day, including an evening arrival. The exceptions are narrow: regular commuters from Canada/Mexico, under-24-hour transits between two foreign points, crew of foreign vessels, days trapped by a medical condition that arose in the US, and exempt-individual days (students/teachers on qualifying visas).

curl -s https://xearno.tools/api/v1/tools/us-substantial-presence-test \ -H 'content-type: application/json' \ -d '{"status":"none","exemptYears":0,"daysCurrent":120,"daysPrior1":120,"daysPrior2":120,"closerConnection":"unsure"}'