L1B over 183 days but back home in Canada weekly

[Jonathanwang]

Hello,
I am working for a global company in Canada as Canadian paid salary employee, I have been travelling on L1B weekly (Monday ~ Thursday for work) to US and working on different US customer projects managed by US sister company in the last couple years. Again, all salary & bounds are from Canadian company only (CAD company charges US sister company), have family and house in Canada only and not over 183 days.
However, I will be over 183 days this year but still travelling weekly (Sunday night ~ Thursday) and have couple questions below.
1. I shall file CAD tax return next year for 2014 as CAD resident and my company is responsible to file US non-resident tax on my behalf, is that right?
2. How can I make sure my company both in CAN & US don’t miss anything that will cause problems later to me personally? Or shall I file 1120F myself?
3. Will that impact to my L1B extension next year?
Any feedback would be highly appreciated.
Jonathan

[nelsona]

1. That is up to the company, but if you need to pay tax, it will be credited on your return, so I doubt that the company will pay the tax and not ask it back from you.
2. You aren't a corporation, they are. let them worry about it.
Just make sure you file 1040NR
3. no

[Jonathanwang]

Two more questions if you don’t mind-
1. I didn’t file 1040NR in previous year, is that Ok? Will that get me into trouble?
2. I found additional information on 183 days in the link below,
It mentions do not count days in US during which: “you are commuter from a residence in Canada or Mexicoâ€￾, if that is correct information, I am less than 183 days this year as I don’t need to count 1 day per week due to weekly traveling. Is that right?
http://www.irs.gov/Individuals/Internat ... sence-Test
However, I am still over 183 days based on substantial presence test even I am not over 183 this year based on exception mention above this year and years before but I probably pass substantial presence test this year and even year before….but my company never mentioned this rule to me before, am I in trouble? Or based on US & Canada income tax treaty plus I have no US source income, I am OK?
thanks again!
Jonathan

[nelsona]

Both you and your firm have tax liability in the US.

You because your work in US has put you there for more days per year than 183, and your firm because your presence has created -- if one did not exist already -- a fixed based in US.

besides, you say you are entering on L status. That pre-supposes that your firm has a very close relationship with this US form, so they already have a base in US, so are probably liable for tax in US for the work you are doing.

They should consult with a cross-border specialist to iron this out.