Illinois 119th Congressional District Boundaries for 2025-2026

A shapefile containing the geographic boundaries for Illinois's congressional districts for the 119th U.S. Congress, seated from January 2025 through December 2026. The data is part of the U.S. Census Bureau's TIGER/Line series, designed as a standalone extract from the national MAF/TIGER System. Boundaries reflect state-provided information as of May 31, 2024.

Use Cases

• Map Illinois congressional district polygons for demographic analysis or political campaign planning.
• Analyze geographic coverage, noting areas assigned the 'ZZ' code where no district was defined by the state's Redistricting Data Program participant.
• Combine this shapefile with other state files to create a national map of 119th Congressional District boundaries.
• Perform spatial joins with demographic data using the district geometry to calculate population statistics.

Strengths

• Boundaries are based on official state-provided information to the Census Bureau by May 31, 2024.
• Data is part of the national TIGER/Line system, designed to be a seamless file with no overlaps or gaps when combined.
• Specifically covers the 119th Congress session, providing current boundaries for the 2025-2026 term.

Limitations

• In parts of Illinois, the Redistricting Data Program participant did not define districts, resulting in areas coded 'ZZ' treated as a single district.
• The dataset is a snapshot; boundaries may be subject to legal challenges or updates after the May 2024 cutoff.
• No attribute columns or sample data are provided in the input, limiting understanding of non-geometric features.

Provenance

Source

U.S. Census Bureau, Department of Commerce

Collection Method

Extracted from the Master Address File / Topologically Integrated Geographic Encoding and Referencing (MAF/TIGER) System.

Time Range

Covers the 119th Congress, seated from January 2025 through December 2026.

Freshness

Last updated on 2025-12-26, reflecting boundaries for the upcoming 119th Congress.

Geography

State of Illinois, United States.