Do I need Form 8840?
Checked for the 2026 tax year · Updated October 2026
Probably, if you spend more than about 4 months a year in the US. You need it if you were in the US at least 31 days this year and your IRS day count reaches 183, while staying under 183 days in the year itself.
The short answer
You likely need Form 8840 if both of these are true:
- You were in the US 31 days or more this year, and
- Your days add up to 183 or more using the IRS formula below.
Snowbirds who spend more than about 4 months a year down south, every year, often cross that line without realizing it.
The IRS formula
The IRS calls this the substantial presence test. Add up:
- Every day you were in the US this year, plus
- One third of your days last year, plus
- One sixth of your days the year before that.
Any part of a day counts as a full day, including the days you arrive and leave.
Margaret was in the US fewer than 183 days in 2026 itself, but her count is over 183. She should file Form 8840 for 2026.
Bob is under the limit, so he doesn't need to file for 2026. If he stays a few more days next winter, that could change.
What Form 8840 does
If your count reaches 183, the IRS can treat you as a US resident for tax purposes. Form 8840, the Closer Connection Exception Statement for Aliens, tells the IRS that your real home is in Canada. Filing it on time protects you from being taxed as a US resident.
You can use it if, for the year:
- You were in the US fewer than 183 days in that year itself,
- Your home and your main ties (family, belongings, bank, health plan) were in Canada, and
- You didn't apply for, or take steps toward, a US green card.
When it's not the right form
- 183 days or more in the year itself. The closer connection exception isn't available. A cross-border tax professional can look at other options, such as the Canada–US tax treaty.
- US income, such as rent from a US property or US wages. Form 8840 then goes with a US tax return (Form 1040-NR), which is a job for a cross-border accountant.
- A green card application, or Canada wasn't your home all year.
When is it due?
If you aren't filing a US tax return, mail Form 8840 to the IRS by June 15 of the following year. For 2026, that's June 15, 2027. See where to mail Form 8840 from Canada.
What if I missed a year?
File as soon as you can. The IRS can refuse the exception for a late form unless you show you didn't know you had to file and took reasonable steps once you found out. If you've missed several years, speak with a cross-border tax professional.
Filing as a couple
Each person needs their own form. See Form 8840 for couples.
Onward is an independent Canadian service, not the IRS. This page explains the rules in plain terms; it isn't tax or legal advice. If your situation is unusual, speak with a cross-border tax professional.