Posted: Mon Apr 21, 2008 10:43 am-
http://www.cra-arc.gc.ca/E/pub/tg/p151/README.html
For all the good it does you. Basically yes, you can carry on paying Canadian taxes and you have to if you have residential ties to Canada. That pamphlet was written jointly by the CRA and the IRS - each has their own definition of residency, that pamphlet is a bit vague on pointing that out.
But you also have to file a US return, and attach relevant bits of paperwork depending on how long you are in the US, which basically tells the IRS to send your money to Ottawa. How you do it depends on how long you stay.
Although basically for 99.9% of cases you file a 1040NR and either an 8840 or an 8833 to claim the tax treaty exemption. (In practical terms it makes little difference which form you use, either 8840 or 8833, the IRS has separate forms because they are separate laws, but the effect is the same).
The more I read about it the more I come to the conclusion that moving your tax home to the US is an extraordinarily bad idea. You will pay less tax, because their taxes are lower, but if you move your tax home to the US it is a very messy business to move it back to Canada later on. Generally speaking carry on paying taxes in Canada unless you are 100% sure you are going to remain in the US forever, or at least primarily.
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Steve.