Montana 183-Day Rule: Does Day Count Even Apply?

Montana's actual test

Under ARM 42.15.109, implementing Mont. Code Ann. §15-30-2101, an individual is a Montana resident for income tax purposes if domiciled in Montana or if the individual maintains a permanent place of abode in Montana. Unlike most states, Montana's rule does not pair the permanent-place-of-abode prong with a codified day-count threshold; residency for the abode prong is instead determined, per the regulation's own language, 'in light of all facts and circumstances.'

Presumptions

None published as a distinct numeric presumption. The general residence statute's 'claim a residence for any purpose, and it's your residence for all purposes' rule functions as Montana's closest analog to a presumption: registering to vote, obtaining a resident hunting or fishing license, or otherwise claiming Montana residency for an unrelated purpose can be used as evidence of Montana domicile for tax purposes.

Domicile controls instead

'Domiciled' is defined by ARM 42.2.304 as having a residence in Montana as determined under Mont. Code Ann. §1-1-215, the state's general residence statute. That statute treats residence as the place a person returns to in seasons of repose when not called elsewhere for labor or a special or temporary purpose, holds that a person can have only one residence, that a residence cannot be lost until another is gained, and, notably, that if a person claims a Montana residence for any purpose, that location becomes the person's residence for all purposes absent a specific statutory exception. A change of residence requires the union of act and intent, not one alone.

Methodology and sources

The threshold, presumption, and rule text shown here come directly from Montana's researched dossier, reviewed against 12 primary sources including Montana Department of Revenue. This is general information, not tax or legal advice.

183-Day Rule Checker

Check your day count against Montana's actual rule.

Jurisdiction

Entry method

Days spent in Montana this tax year

Domicile controls

No statutory day-count test applies

Days counted

0

This jurisdiction does not run a bright-line day-count residency test. Domicile, the place you treat as your true, fixed, permanent home, controls instead, regardless of how many days you spend here.

Montana's actual test

Under ARM 42.15.109, implementing Mont. Code Ann. §15-30-2101, an individual is a Montana resident for income tax purposes if domiciled in Montana or if the individual maintains a permanent place of abode in Montana. Unlike most states, Montana's rule does not pair the permanent-place-of-abode prong with a codified day-count threshold; residency for the abode prong is instead determined, per the regulation's own language, 'in light of all facts and circumstances.'

Presumptions

None published as a distinct numeric presumption. The general residence statute's 'claim a residence for any purpose, and it's your residence for all purposes' rule functions as Montana's closest analog to a presumption: registering to vote, obtaining a resident hunting or fishing license, or otherwise claiming Montana residency for an unrelated purpose can be used as evidence of Montana domicile for tax purposes.

General information based on published dossier research, not tax or legal advice. Consult a qualified advisor before relying on a day count for a filing position.

Montana Day-Count FAQ

Does Montana use the 183-day rule?+

No. Montana's residency test is domicile or maintaining a permanent place of abode in the state, but unlike most states, the permanent-place-of-abode prong has no codified day-count number at all. The Department looks at all the facts and circumstances of how the home is used rather than counting to a specific threshold like 183 days.

How long do I have to get a Montana driver's license and register my car after moving here?+

Both are generally due within 60 days of establishing Montana residency.

Does Montana have a declaration of domicile like Florida?+

No, not for tax purposes. Montana does have a separate homestead declaration, a recorded filing with the county clerk that protects home equity from creditors, but it's a creditor-protection tool under Mont. Code Ann. §70-32-104, not a tax-domicile filing, even though a dated, recorded declaration can support a residency timeline.

I own a home in Whitefish or Big Sky but I'm domiciled elsewhere. How long can I stay before Montana taxes me?+

There's no specific day number to watch, which cuts both ways. Because Montana's permanent-place-of-abode test has no codified day-count threshold, the Department weighs the full facts and circumstances, how the home is used, how much time you actually spend there, and your other ties, rather than applying a bright-line day count like 183.

Read the full Montana residency guide

Day count is one part of the picture. The full guide covers domicile, exit audit risk, the establishment checklist, tax profile, and special situations for Montana.

Open the Montana residency guide