Montana Building Codes

Current base code, county-level adoption data, special-zone overlays, and source links for restoration contractors.

Building Code Portal State Statutes

Counties

ZIPs

411

Special zones

423

Local amendments

Current State Code

Verified state-level adoption record from SkyCanvass jurisdiction data.

Adoption model

municipal_adoption

Base code

irc_2021

Effective date

2024-01-01

Next update

Not scheduled

Montana has NO mandatory statewide residential building code. Code adoption is local option. Climate Zones 6B/7. Heavy snow loads (50-150+ psf). Ice barrier required. Seismic SDC varies (B-D). 56 counties.

County Guides

County pages include local code editions, amendment flags, and jurisdiction-specific links.

Montana Building Codes

Current State Code

County Guides

Beaverhead County

Big Horn County

Blaine County

Broadwater County

Carbon County

Carter County

Cascade County

Chouteau County

Custer County

Daniels County

Dawson County

Deer Lodge County

Fallon County

Fergus County

Flathead County

Gallatin County

Garfield County

Glacier County

Golden Valley County

Granite County

Hill County

Jefferson County

Judith Basin County

Lake County

Lewis and Clark County

Liberty County

Lincoln County

Madison County

McCone County

Meagher County

Mineral County

Missoula County

Musselshell County

Park County

Petroleum County

Phillips County