Illinois’ post-2020 congressional map was enacted through the regular legislative process after the state lost one U.S. House seat in reapportionment. The map has remained in place without court-ordered changes. Lawmakers approved a new 17-district plan in late October of 2021, and the governor signed it into law on November 24, 2021.

The Illinois legislature enacted two sets of state legislative maps during the 2020 redistricting cycle. This was due to the late delivery of U.S. Census data during the Covid public health emergency. Under Illinois law, the legislature would forfeit its right to draw the maps if they were not enacted before a June 30 deadline. According to the state constitution, if that deadline is missed, an eight-member commission must be created to draw a map. Accordingly, the General Assembly first passed House and Senate maps using census survey estimates in June 2021, then revised them after the release of 2020 census data and enacted adjusted plans on September 24, 2021.  Multiple federal lawsuits (including McConchie, Contreras, and East St. Louis NAACP) alleged malapportionment, racial gerrymandering, and vote dilution under Section 2 of the Voting Rights Act. A three-judge court later issued a final order on December 30, 2021, declining to adopt plaintiffs’ proposals and leaving the enacted September plans in place for the 2022 cycle.

last updated: October 2025