Topic no. 851, Resident and nonresident aliens

Because residents and nonresident aliens are taxed differently, it's important for you to determine your tax status.

Nonresident aliens

You're considered a nonresident alien for any period that you're neither a U.S. citizen nor a resident alien for tax purposes.

Resident aliens

You're considered a resident alien for a calendar year if you meet the green card test or the substantial presence test for the year.

Green card test

You're considered to have met the green card test, and are therefore a resident alien, if at any time during the calendar year you are a lawful permanent resident of the United States according to the immigration laws, and this status hasn't been revoked or administratively or judicially determined to have been abandoned.

Substantial presence test

You satisfy the substantial presence test, and are therefore treated as a resident alien for a calendar year, if you have been physically present in the United States on at least: