The Addressing Office provides an efficient and uniform location identification system for the provision of emergency services. The Office is responsible for the assigning addresses in Lewis and Clark County and the incorporated cities of Helena and East Helena. Duties include maintaining address and road databases, reviewing applications, and sharing information with service providers. 

Resolutions and Conventions

Site Address and Road Naming Conventions(PDF, 409KB)

Resolution 2024-59(PDF, 31KB)
Rescinding resolutions 2004-16 and 2021-63 and creating site address and road naming conventions 

Emergency Response Number(PDF, 166KB)

Addressing Conventions(PDF, 106KB)

Street Type Designations(PDF, 267KB)

Master Street Address Guide(XLSX, 161KB) (MSAG)
Spreadsheet of road names in Lewis & Clark County.

Approved/Reserved Road Names(XLSX, 23KB)
Spreadsheet of approved/reserved roads that have yet to be final platted.