(1) Part-year residents and nonresidents are subject to the same filing requirements as residents unless otherwise expressly exempted in statute.

(2) Part-year residents and nonresidents must include all Montana source income on Schedule IV of Form 2. Montana source income is defined in 15-30-2101, MCA.

(3) Part-year residents and nonresidents compute their tax liability by multiplying the ratio of their Montana source income to income from all sources by the tax determined as if they were a resident for the entire tax year. They must complete Schedule IV, Nonresident/Part-Year Resident Tax, to determine this ratio.

(4) Part-year resident and nonresident estates and trusts are subject to the same filing requirements set forth in (1) through (3) unless otherwise expressly exempted in statute.