County seat: Helena
Building in Lewis and Clark County
How zoning works here
This county zones only parts of the unincorporated county — typically specific districts, planning areas, or a buffer around a city. Whether a particular parcel is zoned has to be confirmed with the planning office.
Lewis and Clark County has two types of zoning: citizen-initiated Part 1 zoning districts (standalone rules for each) and county-initiated Part 2 zoning covering the Helena Valley, Fort Harrison Rural Growth Area, and Fort Harrison Urban Growth Area; large portions of unincorporated county remain unzoned.
Building permits
Building permit authority is not verified for this county
Lewis and Clark County does NOT have a certified county building department. Building permits for non-exempt structures in unincorporated Lewis and Clark County are issued by the Montana State Building Codes Bureau (DLI). Within the City of Helena, the City of Helena Building Division issues permits. The county CDP uses a Construction Checklist (revised 2016) that references the state building codes contact at 406-841-2040.
Who to call
Building permits
Montana Department of Labor & Industry Building Codes Program (state authority for unincorporated Lewis and Clark County)
Floodplain administrator
Lewis and Clark County Community Development and Planning (Floodplain Development)
Subdivision review
Lewis and Clark County Community Development and Planning (CDP)
State building codes
Montana Department of Labor and Industry, Building Codes Bureau
Cities with their own jurisdiction
Inside these limits the municipality, not the county, is generally the planning and permitting authority: Helena, East Helena.
Check a specific parcel in Lewis and Clark County
County rules are only part of the picture. Terrain, soils, septic feasibility, flood, wetlands and access are parcel-specific.
County authority details researched from primary county sources and verified 2026-08-14. County rules change and this page is a starting point, not a determination. Confirm anything you intend to rely on directly with the office that administers it. Sources: www.lccountymt.gov, www.lccountymt.gov, www.lccountymt.gov, www.lccountymt.gov