Chicago community areas (CCAs) are 77 areas (originally 75) that were defined by the University of Chicago’s Social Science Research Committee in the 1920s. The purpose of the CCAs is to allow the comparison across time (especially across decennial censuses) of demographic characteristics in areas with stable boundaries. Other small areas, such as wards (with politically changing boundaries) and neighborhoods (with popularly shifting boundaries), do not serve this purpose. There have been only two changes in CCA boundaries since the 1920s: the addition of the O’Hare CCA in the 1950s and the separation of the Edgewater CCA from the Uptown CCA in 1980.

Source of definition: Encyclopedia of Chicago. Entry: Community Areas

Date of definition: January 2016

Note on number of CCAs and yearly changes in CCAs: There are 77 Chicago community areas. The number and boundaries of these areas do not change from year to year.

Note on data availability by CCA: Beginning with data for 2015, IECAM will make most data types available by Chicago community areas.

Note: View a list of Chicago community areas:

Web Resources: Geographic Regions