Most recently Canada and US border control has started sharing information to track when you enter and exit each country. In the past this was never shared so there was no way for each country to know when you left and no way to count your days. The rules have not changes, they are just now enforcing the amount of time people are spending in the US. If you spend significant time in the US, the IRS requires you to prove to them that you have a “Closer Connection” to Canada. Here is how the IRS states it:
You will be considered a US resident for tax purposes if you meet the substantial presence test for the calendar year. To meet this test, you must be physically present in the United States on at least:
- 31 days during the current year, and
- 183 days during the 3-year period that includes the current year and the 2 years immediately before that, counting:
- All the days you were present in the current year, and
- 1/3 of the days you were present in the first year before the current year, and
- 1/6 of the days you were present in the second year before the current year.
To determine if you meet the substantial presence test for 2015, count the full 120 days of presence in 2015, 40 days in 2014 (1/3 of 120), and 20 days in 2013 (1/6 of 120). Since the total for the 3-year period is 180 days, you are not considered a resident under the substantial presence test for 2015. And that means you are not taxable.
If you maximize the 182 day allotment each year, you will be taxable in the eyes of the IRS, but don’t worry, in this case you simply need to file IRS Form 8840 to prove a closer connection to Canada and avoid paying US taxes. This is a simple form to show your primary residence is in Canada and you can file it yourself. You can download the form here: