In many cases, yes! If you had US income during the year, then you usually need to file a US tax return. This is often true even if the amount of income was small. The most common types of US income include: Rental income [...]
If you are an alien (not a US citizen), you are considered a nonresident alien unless you meet one of two tests: The green card test or The Substantial Presence Test for the calendar year (January 1-December 31). For details on how these tests [...]
US nonresident tax returns (Form 1040NR) do not allow you to file jointly. However, if your spouse is a US tax resident and you wish to file jointly, you can make a special election to be treated as a US tax resident. Then, you [...]
I came to the US on business trips, but my salary was paid entirely by my employer in my home country. So, my income is not US income, right?
Actually, your salary from days worked in the US is considered US income! It doesn’t matter where you were paid or where your employer is located. It only matters where you were when you conducted the work. Days in the US for work, training, [...]