Posted: Thu Aug 07, 2008 11:08 am-
http://www.cra-arc.gc.ca/E/pub/tg/p151/README.html
If you're going there temporarily the California rate is irrelevant as it's probably lower than in BC and you claim a foreign tax credit in Canada for the tax paid in the US. Bit tricky for California as they have a significant State income tax, but I'm pretty sure you can claim a credit for it in BC.
But long story short you end up paying the rate in BC overall after you pay in the US and deduct it from your Canadian taxes.
It is not a wise idea to move your tax home to the US for a great many reasons which you can research in the various threads on this forum where people have run into problems doing it. Only makes sense if (a) you are 100% certain you will be able to stay permanently and you plan on doing that; or (b) if you save enough money on taxes to pay a really good cross-border accountant familiar with all the forms.
Top ten reasons not to do it (many others):
1. US authorities hate people moving their tax home to the US and then moving it back to their home country, and then at some future date moving it back to the US again (in fact they generally won't let you do it if you gave up LPR status to move your tax home out of the US);
2. Creates a wide variety of complications with RRSPs, RRIFs, and RESPs;
3. Exposes you to payment of departure tax in Canada (most people aren't subject to it but it isn't fun if you are);
4. Makes your CPP a mess with the totalization agreement (and note that Social Security tax in the US is much higher than CPP contributions in Canada, so it gives you a false impression merely to compare income tax rates);
5. If you are in TN-1 status and move your tax home to the US you are violating the "bona fide non-immigrant intent" provision for TN-1 status;
6. Requires you to file a dual-status return in the US in the first year (unless you move your tax home on January 1st), which means three tax returns, a T1, 1040NR and 1040 - and you have to do it again when you leave, plus a 1040-C in many cases;
7. Exceptionally complex to do it if you own a CCPC as your corporation will be exposed to full corporate tax rates and you will almost certainly be hit with departure tax;
8. Very easy to forget to fill in some important piece of paperwork and get hit with some sort of tax penalty;
9. Very easy to forget to fill in some important piece of paperwork and be prosecuted for a criminal offence, the FBAR form (which is not an IRS form) is a good example (requires you to declare foreign bank accounts outside the US worth more than $10,000);
10. Requires you to cut residential ties to Canada (including giving up healthcare);
11. Easy victim for crappy accountants.
The only real advantage is that you pay less tax. Personally looking at how much healthcare costs in the US plus the various disadvantages I don't think it's worth it, especially if your tax home is Alberta or BC as the tax rates are relatively low in those two Provinces.
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Steve.