Fox Lake is a census-designated place (CDP) in Richland County, Montana, United States. The population was 158 at the 2010 census.
Fox Lake is located at 47°41′3″N 104°37′30″W / 47.68417°N 104.62500°W / 47.68417; -104.62500 (47.684208, -104.625103), 21 miles (34 km) west of Sidney on Montana Highway 200 near the Fox Lake Wildlife Management Area.
According to the United States Census Bureau, the CDP has a total area of 5.7 square miles (14.8 km²), of which, 4.2 square miles (10.9 km²) of it is land and 1.5 square miles (3.9 km²) of it (26.14%) is water.
As of the census of 2000, there were 157 people, 58 households, and 41 families residing in the CDP. The population density was 37.3 people per square mile (14.4/km²). There were 64 housing units at an average density of 15.2 per square mile (5.9/km²). The racial makeup of the CDP was 98.73% White, and 1.27% from two or more races. Hispanic or Latino of any race were 1.27% of the population.
There were 58 households out of which 46.6% had children under the age of 18 living with them, 63.8% were married couples living together, 3.4% had a female householder with no husband present, and 29.3% were non-families. 29.3% of all households were made up of individuals and 15.5% had someone living alone who was 65 years of age or older. The average household size was 2.71 and the average family size was 3.39.
In the CDP, the population was spread out with 36.9% under the age of 18, 2.5% from 18 to 24, 31.2% from 25 to 44, 17.2% from 45 to 64, and 12.1% who were 65 years of age or older. The median age was 30 years. For every 100 females, there were 101.3 males. For every 100 females age 18 and over, there were 94.1 males.
The median income for a household in the CDP was $31,000, and the median income for a family was $36,667. Males had a median income of $21,250 versus $19,250 for females. The per capita income for the CDP was $14,443. About 11.4% of families and 16.2% of the population were below the poverty line, including 27.7% of those under the age of eighteen and none of those sixty five or over.