COUNTY · MT
Granite County, Montana
Granite County is a county in Montana with FIPS code 30039 and an estimated population of 3,595 (Census 2023), 40th largest of 56 in the state.
County facts
- Name
- Granite County
- State
- Montana
- Type
- county
- FIPS code
- 30039
- State FIPS
- 30
- Population (2023)
- 3,595
- Change since 2020
- +8.5%
- State rank
- 40 of 56
Population is the Census Bureau’s Vintage 2023 estimate.
Questions
What is the FIPS code for Granite County?
Granite County, Montana has the five-digit FIPS code 30039: 30 for the state and 039 for the county.
What state is Granite County in?
Granite 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.