Nonresidents and part-year residents must file the Maine resident long form supplemented by Schedule NR or Schedule NRH. Schedules NR and NRH are used to separate Maine-source income or loss from non-Maine-source income or loss and to compute the nonresident credit. A copy of the federal income tax return (Form 1040) and Schedule A (if itemized deductions are claimed on the Maine return) must be attached. The taxpayer must submit a copy of any other federal forms or schedules that the Assessor deems necessary to determine Maine-source income.
18- 125 C.M.R. ch. 806, § 07