Generally speaking, if you get a W-2, you should pay taxes to the US, and if you get a T4, you should pay taxes to Canada. If you're living long term in Canada

Generally speaking, if you get a W-2, you should pay taxes to the US, and if you get a T4, you should pay taxes to Canada. If you're living long term in Canada, your employer should have a tax entity in Canada and issue a T4. If you're working in a US resident capacity as a Canadian (i.e. TN or H1B visa), US and Canada have a tax treaty so that you should not be double-taxed, but that assumes you live in US (and all visa-related fine print applies). If you're getting a W-2 and plan to live in Canada for more than 183 days in a year, then you'll probably want to talk to a tax lawyer and an immigration lawyer (preferably together w/ your employer) beforehand to avoid getting yourself and your company into trouble. What this scenario boils down to is that you cannot legally take an american job without proper work authorization as a foreigner, or you might run into issues with USCIS (e.g. being barred from entry into the US in the future). IIRC visas have even more restrictions on where you can work and how long you can live elsewhere, so I'd say if you plan to live in Canada longer than 30 days, you probably should figure this stuff out beforehand.