Yellowstone County, Montana
|Yellowstone County, Montana|
Location in the state of Montana
Montana's location in the U.S.
|Founded||February 26, 1883|
2,649 sq mi (6,861 km²)
2,635 sq mi (6,825 km²)
14 sq mi (36 km²), 0.52%
|Time zone||Mountain: UTC-7/-6|
Yellowstone County is a county located in the U.S. state of Montana. As of the 2012 United States Census Bureau Estimate put its population at 151,882; it is the most populous county in Montana. Its county seat is Billings. Yellowstone County is named for the Yellowstone River which roughly bisects the county from southwest to northeast. The river in turn was named after the yellow Sandstone cliffs in what is now Yellowstone county.
According to the United States Census Bureau, the county has a total area of 2,649 square miles (6,860 km2), of which, 2,635 square miles (6,820 km2) of it is land and 14 square miles (36 km2) of it (0.52%) is water.
Major highways 
- Interstate 90
- Interstate 94
- U.S. Highway 12
- U.S. Highway 87
- U.S. Highway 212
- U.S. Highway 310
- U.S. Highway 312
- Montana Highway 3
- Montana Highway 47
Adjacent Counties 
- Musselshell County - north
- Rosebud County - northeast
- Treasure County - east
- Big Horn County - south & southeast
- Carbon County - southwest
- Stillwater County - west
- Golden Valley County - northwest
||Golden Valley County||Musselshell County||Rosebud County|
|Stillwater County||Treasure County|
|Carbon County||Big Horn County||Big Horn County|
National protected areas 
As of the census of 2000, there were 129,352 people, 52,084 households, and 34,219 families residing in the county. The population density was 49 people per square mile (19/km²). There were 54,563 housing units at an average density of 21 per square mile (8/km²). The racial makeup of the county was 92.78% White, 0.45% Black or African American, 3.05% Native American, 0.54% Asian, 0.04% Pacific Islander, 1.26% from other races, and 1.87% from two or more races. 3.70% of the population were Hispanic or Latino of any race. 31.1% were of German, 10.4% Norwegian, 9.7% Irish, 9.3% English and 5.4% American ancestry according to the 2000 census.
There were 52,084 households out of which 31.60% had children under the age of 18 living with them, 51.80% were married couples living together, 10.10% had a female householder with no husband present, and 34.30% were non-families. 27.90% of all households were made up of individuals and 10.10% had someone living alone who was 65 years of age or older. The average household size was 2.43 and the average family size was 2.98.
In the county the population was spread out with 25.50% under the age of 18, 9.30% from 18 to 24, 28.70% from 25 to 44, 23.20% from 45 to 64, and 13.30% who were 65 years of age or older. The median age was 37 years. For every 100 females there were 95.20 males. For every 100 females age 18 and over, there were 91.60 males.
The median income for a household in the county was $36,727, and the median income for a family was $45,277. Males had a median income of $33,475 versus $21,566 for females. The per capita income for the county was $19,303. About 8.50% of families and 11.10% of the population were below the poverty line, including 14.50% of those under age 18 and 7.40% of those age 65 or over.
Census-designated places 
Other communities 
Ghost towns\former town sites 
See also 
- List of cemeteries in Yellowstone County, Montana
- List of lakes in Yellowstone County, Montana
- List of mountains in Yellowstone County, Montana
- National Register of Historic Places listings in Yellowstone County, Montana
- Yellowstone County QuickFacts from the US Census Bureau
- "Find a County". National Association of Counties. Retrieved 2011-06-07.
- "Montana Digital Atlas - Montana Natural Resources Information System". Montana State Library, State of Montana. Retrieved 2007-09-27.
- History of Yellowstone as a Place Name
- census.gov Montana population by county, 1900-90 - accessed 2009-05-02
- US Census Population Finder for Yellowstone County - accessed 2010-04-09
- "American FactFinder". United States Census Bureau. Retrieved 2008-01-31.