Cottage Grove is located at . According to the United States Census Bureau, the village has a total area of, all of it land.
Demographics
2010 census
As of the census of 2010, there were 6,192 people, 2,210 households, and 1,628 families living in the village. The population density was. There were 2,289 housing units at an average density of. The racial makeup of the village was 92.1% White, 2.5% African American, 0.2% Native American, 2.2% Asian, 1.1% from other races, and 2.0% from two or more races. Hispanic or Latino of any race were 3.0% of the population. There were 2,210 households, of which 47.1% had children under the age of 18 living with them, 59.4% were married couplesliving together, 9.3% had a female householder with no husband present, 4.9% had a male householder with no wife present, and 26.3% were non-families. 20.2% of all households were made up of individuals, and 9% had someone living alone who was 65 years of age or older. The average household size was 2.80 and the average family size was 3.26. The median age in the village was 33.8 years. 32.5% of residents were under the age of 18; 5.7% were between the ages of 18 and 24; 32.4% were from 25 to 44; 21.7% were from 45 to 64; and 7.7% were 65 years of age or older. The gender makeup of the village was 49.0% male and 51.0% female.
2000 census
As of the census of 2000, there were 4,059 people, 1,427 households, and 1,084 families living in the village. The population density was 1,775.3 people per square mile. There were 1,453 housing units at an average density of 635.5 per square mile. The racial makeup of the village was 95.71% White, 1.82% Black or African American, 0.25% Native American, 0.49% Asian, 0.54% from other races, and 1.18% from two or more races. 1.80% of the population were Hispanic or Latino of any race. There were 1,427 households, out of which 47.3% had children under the age of 18 living with them, 65.0% were married couples living together, 7.5% had a female householder with no husband present, and 24.0% were non-families. 16.1% of all households were made up of individuals, and 6.0% had someone living alone who was 65 years of age or older. The average household size was 2.83 and the average family size was 3.20. In the village, the population was spread out, with 32.1% under the age of 18, 5.6% from 18 to 24, 42.1% from 25 to 44, 14.3% from 45 to 64, and 6.0% who were 65 years of age or older. The median age was 31 years. For every 100 females, there were 102.5 males. For every 100 females age 18 and over, there were 97.3 males. The median income for a household in the village was $66,628, and the median income for a family was $68,667. Males had a median income of $46,190 versus $30,391 for females. The per capita income for the village was $25,777. About 2.7% of families and 3.8% of the population were below the poverty line, including 4.6% of those under age 18 and 12.6% of those age 65 or over.
