j1-status and Canadian residency

[mappiq]

I am a Canadian citizen, studying in Massachusetts, USA (on a J-1 student status). When do I cease to become a resident of Canada?
If I understand correctly, as a J-1 student, I do not become a US resident for tax purposes for the first 5 years (correct? any exceptions?). So does that mean I will remain a resident of Canada until that time?
What choice do I have: can I give up Canadian residency earlier? and/or can I keep my Canadian residency even afterwards?

[nelsona]

You cannot become Cdn non-resident until you are a tax resident of another country. Since IRS rules prevent you from becoming tax resident, and nothing in the treaty over-rides this, you will remain Cdn tax resident until your days in US are 'countable' towards SPT, which is in 5 years.

[mappiq]

Thank you very much nelsona.
Does it make any difference whether I become considered a resident (alien) of Massachusetts before then? (Massachusetts determines residence for tax purposes differently from the US Federal government, so I can - and probably will - be a Massachusetts resident for tax, but not a US resident for tax.)

[nelsona]

No.