Genesee is a census-designated place (CDP) in Jefferson County, Colorado, United States. The population was 3,609 at the 2010 census.
Genesee is located at 39°41′43″N 105°16′2″W / 39.69528°N 105.26722°W / 39.69528; -105.26722 (39.695523, -105.267413).
According to the United States Census Bureau, the CDP has a total area of 6.7 square miles (17 km), all of it land.
As of the census of 2000, there were 3,699 people, 1,511 households, and 1,199 families residing in the CDP. The population density was 555.5 people per square mile (214.4/km²). There were 1,562 housing units at an average density of 234.6 per square mile (90.6/km²). The racial makeup of the CDP was 95.94% White, 0.22% African American, 0.35% Native American, 1.78% Asian, 0.08% Pacific Islander, 0.76% from other races, and 0.87% from two or more races. Hispanic or Latino of any race were 2.73% of the population.
There were 1,511 households out of which 30.1% had children under the age of 18 living with them, 73.9% were married couples living together, 3.6% had a female householder with no husband present, and 20.6% were non-families. 16.2% of all households were made up of individuals and 1.6% had someone living alone who was 65 years of age or older. The average household size was 2.45 and the average family size was 2.73.
In the CDP, the population was spread out with 21.8% under the age of 18, 2.9% from 18 to 24, 25.4% from 25 to 44, 42.2% from 45 to 64, and 7.8% who were 65 years of age or older. The median age was 45 years. For every 100 females, there were 102.4 males. For every 100 females age 18 and over, there were 101.4 males.
The median income for a household in the CDP was $132,077, and the median income for a family was $138,983. The per capita income for the CDP was $79,180. About 1.3% of families and 1.6% of the population were below the poverty line, including 2.6% of those under age 18 and none of those age 65 or over.