Hartland is located at . It is in the Lake Country area of Waukesha County. According to the United States Census Bureau, the village has a total area of, of which, of it is land and is water.
As of the census of 2010, there were 9,110 people, 3,566 households, and 2,440 families living in the village. The population density was. There were 3,746 housing units at an average density of. The racial makeup of the village was 95.1% White, 0.8% African American, 0.3% Native American, 1.7% Asian, 0.1% Pacific Islander, 0.5% from other races, and 1.4% from two or more races. Hispanic or Latino of any race were 2.9% of the population. There were 3,566 households, of which 37.3% had children under the age of 18 living with them, 54.4% were married couples living together, 10.2% had a female householder with no husband present, 3.8% had a male householder with no wife present, and 31.6% were non-families. 26.4% of all households were made up of individuals, and 10.2% had someone living alone who was 65 years of age or older. The average household size was 2.55 and the average family size was 3.12. The median age in the village was 37.5 years. 28% of residents were under the age of 18; 7.3% were between the ages of 18 and 24; 26.4% were from 25 to 44; 28.2% were from 45 to 64; and 10% were 65 years of age or older. The gender makeup of the village was 47.4% male and 52.6% female.
2000 census
As of the census of 2000, there were 7,905 people, 3,002 households, and 2,161 families living in the village. The population density was 1,753.7 people per square mile. There were 3,140 housing units at an average density of 696.6 per square mile. The racial makeup of the village was 97.70% White, 0.28% African American, 0.33% Native American, 0.48% Asian, 0.43% from other races, and 0.78% from two or more races. Hispanic or Latino of any race were 1.51% of the population. There were 3,002 households, out of which 41.3% had children under the age of 18 living with them, 57.4% were married couples living together, 11.0% had a female householder with no husband present, and 28.0% were non-families. 22.3% of all households were made up of individuals, and 7.2% had someone living alone who was 65 years of age or older. The average household size was 2.63 and the average family size was 3.13. In the village, the population was spread out, with 29.7% under the age of 18, 7.8% from 18 to 24, 33.5% from 25 to 44, 21.5% from 45 to 64, and 7.5% who were 65 years of age or older. The median age was 34 years. For every 100 females, there were 93.7 males. For every 100 females age 18 and over, there were 92.7 males. The median income for a household in the village was $58,359, and the median income for a family was $67,844. Males had a median income of $48,475 versus $30,253 for females. The per capita income for the village was $26,537. About 1.8% of families and 2.6% of the population were below the poverty line, including 2.2% of those under age 18 and 3.9% of those age 65 or over.
Nixon Park - land that originally was owned by Dr. H. G. B. Nixon, a doctor whose family settled in Hartland. He donated the land to the village in the 1920s. His old house still stands on Capitol Drive near the downtown area of Hartland.
