S.B. No. 4 is a comprehensive bill that outlines the composition and geographic boundaries of congressional districts in Texas for the election of members to the United States House of Representatives. The bill details the specific counties, tracts, and blocks that make up each district, ensuring clarity in representation and governance. Notably, it establishes definitions for terms such as "tract," "block group," and "block," referencing the 2020 Census TIGER/Line Shapefiles. Additionally, the bill includes a provision to allow for the inclusion of any erroneously omitted geographic areas into the appropriate district, guided by the precedent set in Smith v. Patterson.

Importantly, S.B. No. 4 supersedes all previous enactments regarding congressional districts in Texas, effectively repealing prior acts, including Chapter 7 (S.B. 6) from the 87th Legislature. The new districts will be applicable for elections starting with the primary and general elections in 2026, while the current congressional districts will remain unchanged for the 119th Congress. The bill is designed to take effect immediately upon receiving a two-thirds vote from both houses or, if that is not achieved, will take effect 91 days after the legislative session concludes.