All international student are required to file their taxes if they were in the US during the previous calendar year. Even if you are not employed and have no income, you still have to file your tax.
You will be considered as a resident alien if you have passed the green card test or the substantial presence test for the calendar year.
To meet Substantial Presence Test, you must be physically present in the US at least:
- 31 days during the current year, and
- 183 days during the 3-year period that includes the current year and the 2 years immediately before that, counting:
- All the days you were present in the current year, and
- 1/3 of the days you were present in the first year before the current year, and
- 1/6 of the days you were present in the second year before the current year.
If you are employed:
- Nonresident alien: Form 1040NR. U.S. Nonresident Alien Income Tax Return or Form 1040NR-EZ U.S. Income Tax Return for Certain Nonresident Aliens With No Dependents (if qualified)
- Resident alien: Form 1040EZ, Form 1040A or Form 1040 U.S. Individual Income Tax Return
If you are not employed:
- 8843 form, Statement for Exempt Individuals and Individuals With a Medical Condition