Big Arm, Montana

Big Arm, Montana
Flathead Lake from Big Arm
Location of Big Arm, Montana
Coordinates: 47°47′39″N 114°15′48″W / 47.79417°N 114.26333°W / 47.79417; -114.26333
CountryUnited States
StateMontana
CountyLake
Area
 • Total
5.42 sq mi (14.03 km2)
 • Land5.42 sq mi (14.03 km2)
 • Water0 sq mi (0.00 km2)
Elevation
3,849 ft (1,173 m)
Population
 (2020)
 • Total
218
 • Density40.2/sq mi (15.53/km2)
Time zoneUTC-7 (Mountain (MST))
 • Summer (DST)UTC-6 (MDT)
ZIP code
59910
Area code406
FIPS code30-05800
GNIS feature ID2407837

Big Arm is a census-designated place (CDP) in Lake County, Montana, United States. As of the 2020 census, Big Arm had a population of 218.

The town is situated on the south side of Big Arm, a large bay on Flathead Lake, hence its name. The name was used by the Kootenai people, who lived there prior to the town being established. The post office opened in 1911, with Marion F. Lamb as postmaster.

Big Arm State Park is located just north of the town.