Illinois's congressional districts



Illinois is divided into 17 congressional districts, each represented by a member of the United States House of Representatives. The majority of Illinois' districts are located in the Chicago area.

The Illinois General Assembly has the primary responsibility of redrawing congressional district lines following each decennial census. The governor of Illinois has the power to veto proposed congressional district maps, but the General Assembly has the power to override the veto with the support of 3/5ths of both chambers. In 1971, 1981, and 1991 the General Assembly was unable to come to an agreement, and the map was drawn up by a panel of three federal judges chosen by Democrats and Republicans.

In 2001, the General Assembly was again unable to reach an agreement, and the task of redrawing district boundaries was given to the Illinois congressional delegation. With unified Democratic control of the General Assembly and governor's office during the 2011 and 2021 redistricting cycles, Democrats have been able to redistrict without input from Republicans leading to districts gerrymandered to favor the Democratic Party.

In the 2022 midterm elections, per the 2020 United States census, Illinois lost a congressional seat. From a high of 27 congressional seats apportioned to Illinois following the 1910 and 1930 censuses, the state has lost one to two seats in every reapportionment cycle since 1940 with the exception of the cycle following the 1970 census.

Current districts and representatives
List of members of the United States House delegation from Illinois, their terms, district maps, and the district political ratings according to the CPVI. The delegation in the 118th United States Congress has a total of 17 members, with 14 Democrats and 3 Republicans as of 2023. 

Historical and present district boundaries
Table of United States congressional district boundary maps in the State of Illinois, presented chronologically. All redistricting events that took place in Illinois from statehood in 1818 to 2013 are shown. During the periods of 1863-1873, 1893-1895, and 1903-1948, voters in Illinois elected an additional one to two at-large representatives.

Obsolete districts

 * Illinois Territory's at-large congressional district
 * Illinois's at-large congressional district
 * Illinois's 18th congressional district
 * Illinois's 19th congressional district
 * Illinois's 20th congressional district
 * Illinois's 21st congressional district
 * Illinois's 22nd congressional district
 * Illinois's 23rd congressional district
 * Illinois's 24th congressional district
 * Illinois's 25th congressional district
 * Illinois's 26th congressional district