Indiana’s nine U.S. House districts are drawn through the ordinary legislative process. After the release of the 2020 census data, House Republicans introduced a single redistricting bill -HB 1581- that included both congressional and state-house lines. The House Elections Committee released the draft boundaries, held a handful of hearings across the state, and advanced the bill on September 20, 2021. Five days late, the full House approved the measure, and the Senate amended and passed it on October 1. Governor Eric Holcomb signed it as "Public Law 221-2021" on October 4, 2021. Because Indiana’s constitution imposes no automatic court review and no citizen-initiative referendum, the map took effect immediately.

The same statute set new districts for the 50-member Senate and 100-member House of Representatives. Legislative maps follow identical procedures, committee markup, majority votes in each chamber, gubernatorial signature, but must also respect Indiana’s constitutional rules (single-member districts, population equality, and contiguity). HB 1581 met those standards and, once signed, became law for the 2022 elections. With no independent commission or super-majority requirement, partisan control of the General Assembly effectively shapes the lines.