To file as a dual-status taxpayer, you must file Form 1040, U.S. Individual Income Tax Return. You will also need to attach a statement to your return to show the income for the part of the year you were a nonresident. You can use Form 1040-NR, U.S. Nonresident Alien Income Tax Return as the statement, but be sure to write “Dual-Status Statement” across the top.