You can trigger US tax residency without spending 183 days this year

Snowbird Tax Rules & Form 8840

Wintering in Florida or Arizona feels harmless - until the IRS's Substantial Presence Test counts your days across three years and decides you are a US tax resident. Form 8840 is the simple annual filing that proves your tax home is still Canada. We run your day count and file it.

Check My Day Count How the Test Works
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Quick answer

How many days can a Canadian snowbird spend in the US before owing US tax?

The IRS substantial-presence calculation does not simply count the current year's days. It uses the current year and weighted days from the two prior years. Some Canadians can claim the Closer Connection Exception by filing Form 8840 on time and supporting their Canadian ties. If a person is treated as a US nonresident but has US income, a separate Form 1040-NR tax return may also be required. We calculate the day count, review the residence position and identify the forms the facts require.

Residence decision

Day count is the first calculation, not the final answer

  • Confirm current-year US days and weighted days from the prior two years.
  • Identify excluded-day rules before finalizing the count.
  • If under 183 current-year days, test foreign tax home and closer connection.
  • File Form 8840 on time when relying on the closer-connection exception.
  • Review treaty residence and Form 1040-NR separately when US income exists.

The Substantial Presence Test, in Plain English

You are treated as a US tax resident if you are present at least 31 days this year and 183 days under this weighted three-year formula. The weighting is what catches people - you can be well under 183 days this year alone and still cross the line.

100%

of days present this year

1/3

of days present last year

1/6

of days the year before

Example: 120 days each year for three years = 120 + 40 + 20 = 180. Just under. Add a couple of weeks one winter and you are over 183 - a US tax resident on paper, unless you file Form 8840.

Form 8840: Your Closer Connection to Canada

If you meet the test but your home, family, bank accounts, doctors, and life are in Canada, Form 8840 (Closer Connection Exception Statement) lets you stay a non-resident for US tax. It must be filed on time, every year you are at risk. Miss it and become a US tax resident on paper, and your TFSA and Canadian mutual funds suddenly carry US reporting obligations they didn't have before.

  • Run your exact day count across three years and flag your risk
  • Prepare and file Form 8840 with a documented closer-connection position
  • Advise on treaty tie-breaker positions (Form 8833) if days are very high
  • Set up a simple annual routine so it is never missed again
  • If you already missed Form 8840 in a prior year, evaluate Streamlined catch-up before the IRS notices first

Snowbird Tax FAQs

How many days can a Canadian stay in the US?
For tax purposes, residency can trigger at 31 days this year plus 183 under a weighted three-year formula (100% this year, 1/3 last year, 1/6 the year before). Many snowbirds cross it without hitting 183 days in the current year alone. Immigration day limits are separate.
What is Form 8840?
The Closer Connection Exception Statement. If you meet the Substantial Presence Test but your tax home and main ties are in Canada, filing it on time keeps you a US non-resident for tax. File it every year you are at risk.
What if I do not file it?
If you meet the test and do not file 8840 or claim a treaty position, the IRS can tax you as a US resident on worldwide income, with full reporting including FBAR and FATCA. Filing on time prevents this.
Does 8840 affect how long I can visit?
No. It is purely a tax form about income tax residency. How many days you may legally stay is an immigration question with its own rules.

Not sure if you're exposed?

Day counts are only one piece of cross-border exposure. Run the 60-second diagnostic to check FBAR, Form 5472, FinCEN BOI, and E-2 triggers at the same time.

Run the Compliance Diagnostic

Don't Become a US Tax Resident by Accident

A quick call covers your day count and whether you should be filing Form 8840 this year. No commitment.

Discuss the Filing +1-206-209-8210

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By Gurleen Kaur
Founder of Illuminous Accounting. Experience at Deloitte and Grant Thornton.