Montana Statewide Rule
Montana SB 528 Preempts Local ADU Bans Statewide
Key Facts
- Statute
- MCA 76-2-345 (SB 528)
- Effective
- 2023 session
- Owner occupancy
- Cannot be required
- Parking max
- One space
Summary
Montana SB 528, codified in 2023, requires cities and counties to allow accessory dwelling units on lots zoned for single-family use. Local governments cannot impose owner-occupancy, family-only, or excessive parking requirements.
(1) (a) A municipality shall adopt regulations under this chapter that allow a minimum of one accessory dwelling unit by right on a lot or parcel that contains a single-family dwelling. (b) An accessory dwelling unit may be attached, detached, or internal to the single-family dwelling on a lot or parcel.
Full Breakdown
Senate Bill 528 from the 2023 legislature, codified at MCA 76-2-345, mandates that any city or county zoning single-family dwellings must also permit at least one ADU on the same lot, either attached or detached. Local governments cannot require the owner to occupy the primary dwelling, restrict ADU occupancy to family members, mandate more than one parking space for the ADU, or charge separate impact fees beyond actual cost. Setback and height standards must match those for the primary structure. This represents a major statewide preemption of municipal zoning.
Violations & Penalties
Local ordinances conflicting with MCA 76-2-345 are unenforceable. Property owners may seek injunctive relief and attorney fees against non-compliant municipalities.
Frequently Asked Questions
Can my Montana city ban accessory dwelling units?
Can the city require I live on-site to rent my ADU?
Sources
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