Posted: Thu Mar 06, 2008 10:16 am-
You only become a US resident for tax purposes if you don't claim a closer association to Canada via IRS Form 8840. If you're only going for a short period (say a couple of years) it's usually best to stay a resident of Canada for tax purposes as it can save a lot of time and paperwork.
But there are obviously tax advantages to being in the US (i.e. lower rates of tax).
This explains it in simple terms:
http://www.cra-arc.gc.ca/E/pub/tg/p151/p151-07e.pdf
If you remain a resident of Canada for tax purposes, obviously your RRSP is unaffected.
If you become a resident of the US for tax purposes, then income from the RRSP is taxed in the US. And there is no tax advantage to contributing to it anymore as the US doesn't consider it a tax shelter.
http://www.professionalreferrals.ca/article-723.html_________________
Steve.