Transfer of accumulated pension from Canada to US

Does anybody have information whether pension amount accumulated from a Canadian employer can be transferred to new US employer?

Is it allowed? Is it beneficial? How does the currency rate factored in?

Any pros & cons are known?

If its company pension, I don't know how that would be transferable to another company at all. You'd have to ask the pension administrator at your current employer to find out.

You can usually transfer pensions, depends on the pension plan and what method the pension is retained in. There are tax treaty provisions dealing with this, and the treaty changed this year to make it easier to do it, however as the treaty provisions are brand new you would need to deal with a Canadian accountant who does this on a regular basis as only they will know, frankly (emphasis on Canadian). I doubt even the IRS and the CRA have much of a clue at this point and I wouldn't trust the information on their websites unless it specifically says the 2008 tax treaty.

What I do know is that RRSPs are now treated as IRAs under US tax law, assuming you move your tax home to the US (you don't have to unless you're an LPR, you can keep your tax home in Canada and file as a non-resident in the US). You have to file Form 8891 to declare them to the IRS with your 1040 return. However distributions inside the RRSP are no longer subject to US income taxes.

Contributing to them after moving your tax home to the US is a complex issue though, depends on the type of investment, who the investment is held with, whether they are registered in the US and Canada, etc. My personal feeling is that it's probably better just to open up an IRA and no longer contribute to the RRSP (if you even could).

Exchange rates are more to do with the nature of the investment, obviously if you live in the US, investing in Canadian investments may not make as much sense because of the rate fluctuations.