Countryside is a city in Cook County, Illinois, United States. The population was 5,895 at the 2010 census.
According to the 2010 census, Countryside has a total area of 2.88 square miles (7.46 km), all land.
As of the census of 2000, there were 5,991 people, 2,661 households, and 1,604 families residing in the city. The population density was 2,226.7 people per square mile (859.9/km²). There were 2,818 housing units at an average density of 1,047.4 per square mile (404.5/km²). The racial makeup of the city was 92.29% White, 2.15% African American, 0.10% Native American, 1.55% Asian, 2.19% from other races, and 1.72% from two or more races. Hispanic or Latino of any race were 6.84% of the population.
The top four ancestries reported in Countryside as of the 2000 census were Polish (19.4%), German (17.9%), Irish (15.7%) and Italian (10.2%).
There were 2,661 households out of which 23.7% had children under the age of 18 living with them, 46.0% were married couples living together, 10.4% had a female householder with no husband present, and 39.7% were non-families. 34.6% of all households were made up of individuals and 12.3% had someone living alone who was 65 years of age or older. The average household size was 2.25 and the average family size was 2.93.
In the city, the population was spread out with 19.9% under the age of 18, 7.5% from 18 to 24, 28.8% from 25 to 44, 28.0% from 45 to 64, and 15.7% who were 65 years of age or older. The median age was 41 years. For every 100 females, there were 89.9 males. For every 100 females age 18 and over, there were 87.9 males.
The median income for a household in the city was $45,469, and the median income for a family was $64,535. Males had a median income of $46,604 versus $30,148 for females. The per capita income for the city was $25,449. About 2.4% of families and 3.7% of the population were below the poverty line, including 1.8% of those under age 18 and 2.7% of those age 65 or over.