These Block Equivalency Files (BEFs) are the whole 2020 Census tabulation block representations of the 2024 State Legislative District plans as submitted by the states to the U.S. Census Bureau. The .ZIP file contains a national block equivalency file and individual state files for just those eight states that had changes to both their state legislative districts - upper chamber and lower chamber plans (Georgia, Minnesota, Montana, North Carolina, North Dakota, Ohio, Washington, and Wisconsin) and those three states with changes only to their state legislative districts - lower chamber plans (Michigan, New York, and South Carolina). The fields in these files should be imported as text to preserve leading zeros. A new SLDU plan was approved for Michigan after the Census Bureau collected these plans but still prior to the 2024 elections. The Michigan Senate (upper) chamber is not up for reelection until 2026, so that plan is not reflected in the block equivalency files below. It will instead be captured in the 2026 collection cycle. 

In instances where plans included split 2020 Census tabulation blocks, the Census Bureau requested that the state assign the whole block to one district for the purpose of tabulating data. These block equivalency files contain the whole block tabulation plan.

Four states split blocks in their 2024 State Legislative District- Upper Chamber (SLDU) and State Legislative District- Lower Chamber (SLDL) plans: Colorado, Minnesota, North Dakota, and Washington. Additionally, Delaware split a block in their 2024 SLDU plan and Pennsylvania split a block in their 2024 SLDL plan.

• A unique 3-character census code, identified by state participants, is assigned to each state legislative district upper chamber (SLDU) and lower chamber (SLDL) within the state. In Connecticut, Illinois, Massachusetts, Louisiana, New Hampshire, Wisconsin, and Puerto Rico, the state did not assign the current state legislative districts to cover all of the state or equivalent area. The code “ZZZ” has been assigned to areas with no state legislative districts defined (usually large water bodies). These unassigned areas are treated within the state as a single state legislative district for purposes of data presentation.
• Nebraska has a unicameral legislature and the District of Columbia has a single council, both of which the Census Bureau treats as upper‐chamber legislative areas (SLDUs) for the purpose of data presentation. Therefore, there are no data by the lower chamber of the state legislative districts (SLDLs) for either Nebraska or the District of Columbia.
• The state of New Hampshire uses floterial districts in their lower-chamber (SLDL) plan. Floterial districts are overlay districts made up of two or more discrete districts. These discrete or component districts are those represented in the New Hampshire SLDL TIGER/Line shapefile. A listing of the floterial districts and their component districts is available as a PDF and as a comma delimited text file.