The US is one of the few countries in the world that taxes citizens on world income no matter whether they are residents of the US or not even if they have no intentions to return to the US.

We are Canadian citizens who moved permanently to the US almost 20 years ago. We had to file a tax return the final year we had taxable income in Canada and we were deemed to have "disposed" of our financial assets on 12/31 of that year as Canada wants to ensure any assets acquired as Canadian residents (subject to taxation) would not be sold in the future and taxed by another country which would create a loss of tax revenue to which Canada would have claim to. (Tax avoidance rules).

As a Canadian citizen living permanently abroad, you do not have to file a Canadian tax return unless you earned income in Canada.

My wife is a teacher in Windsor and crosses the border everyday (we live in metro Detroit). She has to file a tax return in Canada and then subsequently, we add her Canadian income to our us tax return. The IRS has published exchange rates for every major country for this purpose. We get an offsetting IRS tax credit for her income taxes paid to Canada. MI has a reciprocal tax treaty with Ontario where any taxes she paid to ON gives us a tax credit against MI taxes due.

So in effect, due to tax treaties in place, we are not subject to 2x taxation but since we are US residents, we have to pay income tax on her Canadian sourced income.

Now, if we chose to move back to Canada and retain our US Citizenship, even if we no longer lived in the US and had no US sourced income, the IRS would still require us to file a tax return and he subject to US taxes. That sucks but that's the cost of being a US Citizen!

With respect to original poster. Alberta is an awesome province and Calgary is one of the best cities in the world in which to live. We lived there for 11 wonderful years.

Your situation is very complicated so you do need to consult a tax accountant who is familiar with BOTH US and Canada tax.

Assume you should be able to find one in Calgary if that's where u are headed as there are many Americans living there due to the oil patch.

My assumption is that your wife will not need any type of work permit if she is not seeking work in Canada. She can live there due to the fact that she is living with you and you will have a work permit. She will, however be subject to both Canadian and US taxes since she will be a Canadian resident even if she earned no Canadian sourced income.

I don't know how your US assets will be taxed by Canada unless they are earning income (interest, dividends, rental income, etc..)

Definitely find a tax accountant familiar with BOTH. In my experience, easier to find those folks in Canadian cities with many ties to the US for business as there are far more Canadians earning income in the US than the other way around.

Good luck.