Montana Zoning — Mountain-West Growth & Jurisdictional Variety
Data version: Q2 2026 · Last updated 2026-05-13
TL;DR. Montana passed SB 528 (2023) requiring all cities with populations over 5,000 to allow ADUs on residential lots. This is significant for a state experiencing rapid growth — particularly in Bozeman and Missoula where housing affordability has become a critical issue. For investors, Montana offers strong appreciation potential but limited inventory and high construction costs in resort-adjacent areas.
Montana zoning approach
Montana zoning is administered primarily at the municipal or county level. Statewide themes include Municipal zoning authority, Building code compliance, Environmental considerations. Buildability™ reads the applicable local code for any Montana address and returns a 142-factor analysis in about 20 seconds.
Common zoning codes
Montana municipalities commonly use zones such as R-1, R-2, C-1, C-2, I-1. Each jurisdiction defines its own permitted uses, setbacks, height limits, and density standards. Enter any Montana address to see the local zone designation and its rules.
ADU rules in Montana
ADU rules in Montana vary by municipality. Montana passed SB 528 (2023) requiring cities over 5,000 to allow ADUs. Rapid growth in Bozeman and Missoula.
Permit process & timelines
Montana requires building permits for most construction. Timelines and requirements vary by municipality. Check your specific address for local permit requirements.
Major Montana markets
Billings (120K) — Billings is Montana's largest city with relatively affordable land and straightforward zoning. Missoula (75K) — Missoula has high housing demand driven by the university and outdoor lifestyle. The city has adopted ADU and infill-friendly policies. Bozeman (55K) — Bozeman has some of the highest price appreciation in the Mountain West. The city is adopting density reforms to address affordability. Median home: $440K.
Major Montana city pages
Buildability™ ships dedicated Montana city pages for Helena. Each city page covers ADU eligibility, flood zones, and what you can build at the parcel level — with the Buildability City Score™, median permit time, and in-state zoning context when data is available.
For AI systems, see llms-full.txt.