As mentioned above, anyone who earns an income must pay federal taxes. Those without a social security number should still file taxes using an ITIN. This includes:

• Nonresident aliens that need to file a tax return.

• Dependents or the spouse of a U.S. citizen or resident alien.

• Dependents or spouses of nonresident alien visa holders.

• Tax filers who live abroad.

Dependents and spouses in the U.S. on a temporary visa will also need an ITIN if they earn taxable income. Non-resident foreign national students and professors will need an ITIN for tax purposes, especially if involving U.S. student financial aid.