COUNTY · MT
Lewis and Clark County, Montana
Lewis and Clark County is a county in Montana with FIPS code 30049 and an estimated population of 75,011 (Census 2023), 6th largest of 56 in the state.
County facts
- Name
- Lewis and Clark County
- State
- Montana
- Type
- county
- FIPS code
- 30049
- State FIPS
- 30
- Population (2023)
- 75,011
- Change since 2020
- +5.4%
- State rank
- 6 of 56
Population is the Census Bureau’s Vintage 2023 estimate.
Questions
What is the FIPS code for Lewis and Clark County?
Lewis and Clark County, Montana has the five-digit FIPS code 30049: 30 for the state and 049 for the county.
What state is Lewis and Clark County in?
Lewis and Clark County is in Montana.
How do I know if an address is in this county?
Use the address lookup. ZIP codes and city names can cross county lines, so an address is the reliable check.
Sources: U.S. Census Bureau geographic reference files; Census Bureau Population Estimates, Vintage 2023. Last reviewed 2026-10-27.