Examples of Individuals Who Need an ITIN A nonresident alien individual claiming a tax treaty benefit A nonresident alien filing a U.S. tax return A resident alien (who is treated as a resident alien for income tax purposes based on his or her days of presence in the United States) who files a U.S. tax return A resident or nonresident alien individual who can be claimed as a dependent of a U.S. citizen or resident alien on a U.S. tax return A resident or nonresident alien spouse who isn't filing a U.S. federal tax return (including a joint return) but who can be claimed as a dependent on a U.S. tax return A resident or nonresident alien electing to file a joint tax return with a spouse who is a U.S. citizen or resident alien A nonresident alien student, professor, or researcher filing a U.S. tax return or claiming an exception A resident or nonresident alien individual who can be claimed as a dependent or a spouse of a nonresident alien U.S. visa holder