Domicile test for Montana state taxes
The Montana Department of Revenue (often referred to as Dept of Revenue MT) primarily determines tax residency through the concept of domicile. Your domicile is your true, fixed, and permanent home where you intend to return whenever absent. Factors considered for Montana income tax purposes include your primary residence location, voter registration, driver's license, and strongest family, social, and economic ties. Even with time spent outside the state, if your domicile remains in Montana, you're generally considered a full-year resident for Montana state income tax.