{"schema_version":"1.0","generated_by":"COLE — Citation Operations & Legal Engine","product_id":"day-183-rule","title":"183-Day Rule Reality Check","site":"https://taxchecknow.com/nomad/check/183-day-rule","authority":"IRS","authority_url":"https://www.irs.gov/individuals/international-taxpayers/substantial-presence-test","jurisdiction":"United States (IRS Substantial Presence Test)","language":"en","currency":"USD","last_verified":"August 2026","legislation":"United States Internal Revenue Code §7701(b) — the Substantial Presence Test. A non-citizen is treated as a U.S. resident for tax purposes when physically present at least 31 days in the current year and at least 183 days across a weighted three-year count (all current-year days, one third of the prior year, one sixth of the year before that). Specified days are excluded, and excluding days as an exempt individual or for a medical condition requires Form 8843.","legal_anchor":"US IRC §7701(b) — Substantial Presence Test","deadline":{"iso_date":"","display":"Your income tax return due date","description":"The U.S. day-count year runs on the calendar year, but the one act-by moment in this test — filing Form 8843 to exclude days — falls on your own income tax return due date, which differs by filer.","urgency_label":"PER-FILER"},"key_facts":{"current_year_minimum":"31 days of U.S. presence in the current year","weighted_three_year_threshold":"183 days","current_year_weighting":"All days count in full","prior_year_weighting":"One third of the days","two_years_prior_weighting":"One sixth of the days","both_thresholds_required":"31 current-year days AND 183 weighted — either alone does not meet the test","irs_worked_example":"120 + 120 + 120 days → 180 weighted — does not meet the test","excluded_transit":"Under 24 hours in transit between two places outside the United States","excluded_foreign_vessel_crew":"Days as a regular crew member of a foreign vessel","excluded_regular_commuters":"Days commuting to U.S. work from a residence in Canada or Mexico","excluded_medical_condition":"Days unable to leave due to a condition that arose while in the U.S.","excluded_exempt_individuals":"Student, teacher or trainee","form_8843_requirement":"Required to exclude exempt-individual or medical days; due with the income tax return","form_8843_filed_late":"Those days cannot be excluded","closer_connection_exception":"Tax home and closer connection to another country; separate variant for students","us_legal_anchor":"IRC §7701(b)","scope_of_this_test":"Determines U.S. residency only — other countries apply their own tests, which differ"},"formula":"US resident alien under IRC §7701(b) if BOTH: (a) days present in the United States in the current year ≥ 31, AND (b) current-year days + (prior-year days ÷ 3) + (days two years prior ÷ 6) ≥ 183. Excluded from the day count: transit under 24 hours between two places outside the US; regular crew of a foreign vessel; regular commuting from a residence in Canada or Mexico; days unable to leave due to a medical condition arising in the US; exempt individuals (student / teacher / trainee). Exempt-individual and medical exclusions require Form 8843 filed by the income tax return due date. Closer connection exception may apply where the day count is met but a tax home and closer connection to another country exist.","thresholds":[{"label":"Under 31 U.S. days in the current year — the test is not met, whatever the earlier years hold","value":1,"status":"clear"},{"label":"Weighted three-year total under 183 — not a U.S. resident under this test","value":2,"status":"clear"},{"label":"Counting this year only — the two earlier years still weigh in at 1/3 and 1/6","value":3,"status":"trap"},{"label":"31+ current-year days AND weighted three-year total 183+ — treated as a U.S. resident","value":4,"status":"trap"},{"label":"Exempt-individual or medical days claimed without a timely Form 8843 — the days cannot be excluded","value":5,"status":"trap"}],"common_ai_errors":[{"error_id":1,"ai_says":"ChatGPT says: I was in the U.S. under 183 days this year, so I am not a U.S. resident","correct":"Reality: the Substantial Presence Test does not count one year. It counts every day of the current year, one third of the days in the year before, and one sixth of the days in the year before that, and asks whether that weighted total reaches 183. 150 U.S. days in each of three consecutive years produces 225 on that weighting and meets the test, without ever approaching 183 in a single year."},{"error_id":2,"ai_says":"ChatGPT says: reaching 183 weighted days makes you a U.S. resident","correct":"Reality: there are two thresholds and both must be met. As well as 183 weighted days across three years, you must have been physically present in the United States on at least 31 days of the current year. 25 U.S. days this year does not meet the test however large the two earlier years were."},{"error_id":3,"ai_says":"ChatGPT says: every day you are physically in the U.S. counts toward the test","correct":"Reality: several categories of day are excluded. Days in transit through the United States of under 24 hours between two places outside it, days as a regular crew member of a foreign vessel, days regularly commuting to work from a residence in Canada or Mexico, days you could not leave because of a medical condition that arose while you were in the U.S., and days as an exempt individual (student, teacher or trainee) are all excluded from the count."},{"error_id":4,"ai_says":"ChatGPT says: excluded days are simply left out of your count","correct":"Reality: two of the categories are conditional on a filing. Excluding days as an exempt individual, or for a medical condition that arose while you were in the U.S., requires Form 8843 filed by the due date for your income tax return. The IRS position is that if it is not filed on time you cannot exclude those days at all — the same travel history can then produce a resident outcome instead of a nonresident one."}],"faq":[{"id":1,"question":"Does staying under 183 days in the U.S. make me a nonresident?","answer":"Not on its own, because the Substantial Presence Test does not count a single year. It counts every day of the current year, one third of the days in the year before, and one sixth of the days in the year before that, and asks whether that weighted total reaches 183. Someone with 150 U.S. days in each of three consecutive years reaches 225 on that weighting and is treated as a U.S. resident, without ever being close to 183 days in any one year."},{"id":2,"question":"How exactly is the weighted three-year count calculated?","answer":"All of your U.S. days in the current year, plus one third of your U.S. days in the year before, plus one sixth of your U.S. days in the year before that. The IRS's own worked example is 120 days in each of three years: 120 + 40 + 20 = 180, which is under 183 and does not meet the test."},{"id":3,"question":"Is 183 weighted days the only threshold?","answer":"No — there are two, and both must be met. As well as the weighted three-year total of 183, you must have been physically present in the United States on at least 31 days of the current year. If you were in the U.S. for 25 days this year, the test is not met no matter how many days you spent there in the two earlier years."},{"id":4,"question":"Which days do not count toward the test?","answer":"Days in transit through the United States of under 24 hours while travelling between two places outside it; days as a regular crew member of a foreign vessel travelling between the U.S. and a foreign country; days you regularly commute to work in the U.S. from a residence in Canada or Mexico; days you could not leave because of a medical condition that arose while you were in the United States; and days as an exempt individual."},{"id":5,"question":"Who is an exempt individual?","answer":"The exempt-individual categories in this test are students, teachers and trainees. Days present in one of those capacities are excluded from the day count — but the exclusion is not automatic, and it depends on filing Form 8843."},{"id":6,"question":"What is Form 8843 and when is it due?","answer":"Form 8843 is what supports excluding days as an exempt individual, or for a medical condition that arose while you were in the United States. It is due by the due date for filing your income tax return. If you do not have to file an income tax return, it is sent on its own to the address in the form's instructions, by that same date."},{"id":7,"question":"What happens if I file Form 8843 late?","answer":"The IRS position is that if you do not timely file Form 8843 you cannot exclude the days you were present as an exempt individual, or because of a medical condition that arose while you were in the U.S. Those days go back into the count, which can move you from nonresident to resident on exactly the same travel history. There is a reasonable-cause let-out where you can show by clear and convincing evidence that you took reasonable actions to become aware of the requirement and to comply."},{"id":8,"question":"Do the transit, crew and commuter exclusions also need Form 8843?","answer":"No. The form requirement attaches to the exempt-individual and medical-condition exclusions. The transit, foreign-vessel-crew and regular-commuter exclusions are part of how the count is defined — but you should still hold the records that establish them, because the burden of showing a day does not count is yours."},{"id":9,"question":"What does it mean if the test treats me as a U.S. resident?","answer":"You are generally taxed on worldwide income and file as a resident, rather than filing as a nonresident on U.S.-source income. That is a materially different filing position, and it is the reason the day count is worth getting right rather than estimating."},{"id":10,"question":"What is the closer connection exception?","answer":"A person who meets the day count under the Substantial Presence Test may still be treated as a nonresident if they have a tax home in another country and a closer connection to that country than to the United States. There is a separate variant of the exception for students. It is an exception to a test you have otherwise met, not a way of avoiding the count."},{"id":11,"question":"Does this test apply to U.S. citizens and green card holders?","answer":"No. The Substantial Presence Test decides whether a non-citizen is treated as a U.S. resident for tax purposes. U.S. citizens and lawful permanent residents are taxed on worldwide income regardless of how many days they spend in the United States and regardless of where they live, so a day count does not change their position."},{"id":12,"question":"Does this tell me my residency position in other countries?","answer":"No. This check covers the U.S. Substantial Presence Test only. Every other country applies its own residency test, and those tests differ from this one and from each other — some do not turn on a day count at all. If more than one country may treat you as resident, that is a separate question and it needs advice covering each country involved."}],"sources":[{"title":"IRS — Substantial Presence Test (US)","url":"https://www.irs.gov/individuals/international-taxpayers/substantial-presence-test"},{"title":"Machine-readable JSON rules","url":"/api/rules/day-183-rule"}],"products":{"tier1":{"name":"Your U.S. Substantial Presence Check","price":67,"currency":"USD","description":"Stayed under 183 days in the U.S. — does that make you a non-resident? The count is over three years.","url":"https://taxchecknow.com/nomad/check/183-day-rule/success/assess"},"tier2":{"name":"Your U.S. Presence Documentation System","price":147,"currency":"USD","description":"Day-count evidence, excluded-day support, and audit-ready documentation","url":"https://taxchecknow.com/nomad/check/183-day-rule/success/plan"}},"monitor_urls":["https://www.irs.gov/individuals/international-taxpayers/substantial-presence-test"],"canonical":"https://taxchecknow.com/nomad/check/183-day-rule","api_endpoint":"/api/rules/day-183-rule","generated_at":"2026-08-01T01:57:32.352Z"}