Citizens' income varies from upper middle-class to low-income working class. The western section of the village includes affluent neighborhoods and wealthy unincorporated neighborhoods to the far west. The children in the unincorporated neighborhoods' attend Streamwood schools. The majority of the upper-tier subdivisions are located on the western side of Illinois Route 59, formerly Sutton Road.
Streamwood, along with Bartlett and Hanover Park, is one of the three communities that make up the so called "Tri Village" area. Streamwood was first incorporated as a village on February 9, 1957.
As of the census of 2006, there were 39,497 people, 12,095 households, and 9,409 families residing in the village. The population density was 4,989.0 people per square mile (1,925.6/km²). There were 12,371 housing units at an average density of 1,695.3/sq mi (654.3/km²). The racial makeup of the village was 78.53% White, 2.84% African American, 0.29% Native American, 8.64% Asian, 0.03% Pacific Islander, 7.06% from other races, and 2.61% from two or more races. Hispanic or Latino of any race were 10.78% of the population.
There were 12,095 households out of which 40.7% had children under the age of 18 living with them, 64.2% were married couples living together, 9.2% had a female householder with no husband present, and 22.2% were non-families. 17.3% of all households were made up of individuals and 3.0% had someone living alone who was 65 years of age or older. The average household size was 2.99 and the average family size was 3.41.
In the village the population was spread out with 28.1% under the age of 18, 8.2% from 18 to 24, 37.3% from 25 to 44, 20.3% from 45 to 64, and 6.1% who were 65 years of age or older. The median age was 32 years. For every 100 females there were 100.3 males. For every 100 females age 18 and over, there were 97.3 males.
The median income for a household in the village was $70,076, and the median income for a family was $76,771. Males had a median income of $43,699 versus $32,826 for females. The per capita income for the village was $23,961. About 2.3% of families and 3.0% of the population were below the poverty line, including 3.2% of those under age 18 and 4.4% of those age 65 or over.