Originally Posted by Steve_

It doesn't sound grey to me, the company you work for has no permanent establishment in Canada from the sounds of it, and you're a bona fide visitor for business. If they had a permanent establishment in Canada and you're in Canada more than six months then you would need to think about an intracompany transfer visa. Also, after six months you would become resident in Canada for tax purposes.

Originally Posted by Steve_

I can't really see an issue with your LPR status, if you're out of the US more than 30 months in a 5-year period though, you jeopardize being able to apply for US citizenship.

Originally Posted by Steve_

Your real problem is the tax situation. The US-Canada tax treaty has various exemptions, the main one being for people who are in Canada for less than six months. You don't want to become resident in Canada for tax purposes for obvious reasons, and you cannot become resident for tax purposes in another country while you are an LPR of the US, because the US means what it says on that score - "permanent resident" means exactly that, your tax home is therefore in the US. This is why they ask if you've filed taxes as a non-resident on form N-400.

So long story short, not a problem in the short term, but the longer it goes on the more likely it is to become one.

Bear in mind (because a lot of people don't) that under the tax treaty the IRS and CRA have direct access to each other's tax records. And when I say "direct access" it's not some difficult thing for them to do, it's very straightforward, I know from experience. Do not under any circumstances attempt to mislead or misrepresent anything to either agency, especially the CRA. The basic function of the CRA seems to be to stop tax revenue from going south.

Don't be surprised if you spend a lot of time in Canada that you end up getting an NR74 in the mail at some point. Usually it happens if you open a Canadian bank account, state you're non-resident but use a Canadian address on the account. Or Canadian credit cards, anything like that. As soon as they get the NR4 from the bank they start sniffing around. Even with a US address I wouldn't be surprised if they bang it into their computer and see what pops up.

Originally Posted by Steve_

So you've been an LPR for more than 5 years?

Apply for citizenship. Strongly recommend you do so, because as a US citizen you can move your tax home if you need to, and in addition, "computer system analyst" is a NAFTA category and it sounds as though you may well fit into it. As a business visitor, you're authorized to work in any NAFTA category provided the source of remuneration is outside of Canada and in addition, getting a work permit if you need to will be far easier.

Originally Posted by MVX

I'm not being employed by a Canadian entity. I don't have any financial links to Canada. I don't and won't have a Canadian bank account, credit card or utility bills. I will stay in a hotel or other temporary accommodation so no leases signed. I return to the USA once every few weeks for a week of meetings and debriefings, and I am paid in the USA by a US company so I don't see how I would have any tax status in Canada unless I am missing something.