Tax Questions for Internship on TN Visa. Should I fill out Form 8843?

Question

I worked for 4 months at an internship in Massachusetts in the summer of 2016. I'm a Canadian citizen and resident and have a few questions below. For background, I don't pass the substantial presence test for 2016

1. Do I just need to file Form 1040NR-EZ for federal taxes and Form 1-NR/PY for state taxes, and mail them to their respective addresses? Can I file them at the same time or do I need to wait for the result of one before filing the other?
2. Should I file a form 8843? Or is it irrelevant if I already don't pass the substantial presence test?
3. Do I have to wait until the tax return is processed before reporting the amount on line 61 of Form 1040NR-EZ on my Canadian tax return?
4. Are there any complications I should be aware of for sending in my tax returns late? Or can I just mail the federal/state tax forms separately tomorrow?

Thanks

Answer 1

1. Yes. You just need to file those. You can file them together or in any order.
2. No. You were not an "exempt individual" for any part of the year.
3. I'm not sure about Canadian taxes. You can probably only claim a foreign tax credit for foreign taxes paid during this year when you file this year's taxes next year.
4. Not if you get a refund. If you owe taxes, there may be late fees.