Tax is where this series stops being something we can responsibly summarize. The rules are cross-border, they depend on your visa, and a mistake costs money and sometimes penalties.
We are not accountants. We read the IRS pages on the substantial presence test and the closer connection exception, and we describe what they say. We did not read the Canada-US tax treaty text. Please treat this as a map of questions to take to a cross-border tax professional.
The Core Question
The IRS decides whether a non-citizen is a US tax resident using the substantial presence test. You meet it if you are physically present in the US on at least 31 days in the current year and at least 183 days over a three-year period. The 183 days are counted as all the current-year days, one-third of the prior year’s days and one-sixth of the days from two years earlier. [1]
A resident physician working full time in the US is present for most of the year. By that formula, a full year in the US gives you far more than 183 days, so you would normally expect to meet the test, unless an exemption applies.
Exempt Individuals
The IRS says days spent as an “exempt individual” are not counted. The categories include teachers and trainees on a J or Q visa who substantially comply with the visa requirements, and students on F, J, M or Q visas who do the same. [1] To exclude those days you must file Form 8843, and if you do not file it on time you generally cannot exclude them. [1]
That is the point at which the visa you choose matters for tax as well as immigration. A J-1 resident may be able to treat early days as exempt. The page we read does not state how many years that exemption lasts.
We have heard that the exemption runs out partway through a multi-year residency, but the page does not say that, so we are not going to tell you it is true. Ask a professional.
The Closer Connection Exception
The IRS also describes a closer connection exception, claimed on Form 8840. To use it you must have been in the US fewer than 183 days during the year, maintain a tax home in a foreign country for the entire year, and have a closer connection to that country than to the US. [2]
For a resident physician working most of the year in the US, the fewer-than-183-days condition will usually rule it out. We mention it because forums sometimes suggest it, and we want you to know it has conditions. You also cannot use it if you applied to change your status to lawful permanent resident, which the IRS says includes filing certain forms. [2]
Canada Does Not Automatically Let Go
The IRS test is one half of the picture. The other is whether the CRA still treats you as a Canadian resident. As we explain in our tax residency article, the CRA looks at your residential ties, including a home, spouse or partner and dependants in Canada, and it names attending school in another country as a situation where you may remain a factual resident. [3]
If both countries claim you, treaty rules and foreign tax credits exist to prevent being taxed twice on the same income. We have not read the treaty and we are not going to describe it. The IRS directs people to Publication 901 and the treaty tables for the details of treaty provisions. [4]
What the Forms Are
Without describing every form, the ones that came up in our reading were Form 8843 for exempt individuals, Form 8840 for the closer connection exception, and, on the Canadian side, Form NR73 to ask the CRA for a residency determination. [1][2][3] The IRS says without a timely Form 8843 or 8840 you may lose the exclusion or exception. [1][2]
Why This Matters Beyond the Filing
Your tax status affects your take-home pay, which affects whether a US salary is better than a Canadian one. It affects whether you can keep contributing to Canadian accounts. It may affect your options if you later want to return to Canada.
We cover the salary comparison in our resident salary article and the residency question in our Canadian tax article.
How We Would Handle It
We would book a consultation with a cross-border accountant before starting, not after the first tax year. We would take our visa documents, our lease, our travel history and our Canadian ties with us. We would ask specifically about our visa category, exempt individual status, and how Canada views us.
Accountants who work with international residents do this regularly. Some program offices have a recommended list.
The Bottom Line
A Canadian working full time as a US resident will usually pass the IRS substantial presence test unless an exempt individual rule applies, which depends on your visa and requires Form 8843. The closer connection exception generally needs fewer than 183 days in the US, and the CRA may still treat you as a Canadian resident, so both countries’ rules matter.
Start with the IRS pages and CRA page we link, then see a cross-border tax professional. Our Resources page lists the other sources we trust.
References
- Internal Revenue Service. (2026). Substantial presence test. https://www.irs.gov/individuals/international-taxpayers/substantial-presence-test
- Internal Revenue Service. (2026). Closer connection exception to the substantial presence test. https://www.irs.gov/individuals/international-taxpayers/closer-connection-exception-to-the-substantial-presence-test
- Canada Revenue Agency. (2026). Determining your residency status. https://www.canada.ca/en/revenue-agency/services/tax/international-non-residents/information-been-moved/determining-your-residency-status.html
- Internal Revenue Service. (2026). Tax treaty tables. https://www.irs.gov/individuals/international-taxpayers/tax-treaty-tables