In late 2025, the Census Bureau plans to formally announce the commencement of Phase 1: The Block Boundary Suggestion Project (BBSP) through a Federal Register notice. The purpose of the BBSP is to afford states the opportunity to identify non-standard features often used as electoral boundaries (such as power lines, property lines, or streams) that could be used in conjunction with more traditional features (such as street centerlines) as census tabulation block boundaries. The officially designated state liaison can identify and suggest that some of these features be used as 2030 census tabulation block boundaries, resulting in more meaningful tabulation block data for the state. The liaison may work with local officials, including county election officers and others, to ensure local geography is represented in the 2030 census tabulation block inventory. In addition, the liaison may make suggestions for features not desirable as census tabulation block boundaries.

Beginning in early 2026, the Census Bureau plans to provide to official liaisons from states that choose to participate in Phase 1 guidelines and training. The guidelines and training will explain how the liaisons will provide their suggestions for the 2030 census tabulation block boundaries as well as their suggestions for exclusion of line segments for consideration as 2030 tabulation block boundaries.

States will also have the opportunity to review legal boundaries such as incorporated place and county boundaries, in coordination with the annual Boundary and Annexation Survey (BAS) program. Incorporating the opportunity for states to review legal boundaries was successfully implemented for the first time in the 2020 Redistricting Data Program and proved valuable as these legal boundaries also become census tabulation block boundaries. The Census Bureau plans to process all tabulation block boundary suggestions and provide state liaisons the opportunity to verify them in early 2027.

In late 2027, the Census Bureau plans to formally announce the commencement of Phase 2: The Voting District Project (VTDP) through a Federal Register notice. The VTDP will provide the official state liaisons the opportunity to submit and verify their voting districts (a generic term used to represent areas that administer elections such as precincts, election districts, and wards) to the Census Bureau for inclusion in the 2030 Census Redistricting Data (P.L. 94-171) products (tabulated data and geographic products).

Beginning in early 2028, the Census Bureau plans to begin the initial voting district update cycle, providing to liaisons in states that choose to participate, guidelines and training for submitting their voting district boundaries. The Census Bureau will process the updates and provide states with two opportunities to verify the updates were processed correctly. The first verification cycle is planned for early 2029. The second verification cycle, planned for early 2030, will only be available to states that participated in the initial update cycle or the first verification cycle.

State liaisons will also continue to have the opportunity to make census tabulation block boundary suggestions and to review legal boundaries such as incorporated place and county boundaries in coordination with the Boundary and Annexation Program during the initial update cycle and the first verification cycle.

In accordance with 13 U.S.C. 141(c), the Director of the U.S. Census Bureau will furnish the governor, state legislative leaders of both the majority and minority parties, and any other sitting “officers or public bodies having initial responsibility for the legislative apportionment or districting of each state” with 2030 Census population counts for standard census tabulation areas (e.g., state, congressional district, state legislative district, American Indian area, county, city, town, census tract, census block group, and census tabulation block) regardless of whether or not a state participates in Phases 1 or 2. The Director will also provide 2030 Census population counts for voting districts to any state that participated in Phase 2. Delivery is expected to occur prior to or alongside the public release of the 2030 Census Redistricting Data (Pub. L. 94-171) Summary File, no later than April 1, 2031.

Beginning in 2031, the Census Bureau plans to solicit from each state the newly drawn legislative and congressional district plans based on the 2030 census results and compile population, housing and other data for those new districts. This effort is expected to occur every two years in advance of the 2040 Census in order to update these district boundaries with new or changed plans. A verification phase is planned to occur with each two-year update cycle.

As the final phase of the 2030 Census Redistricting Data Program, the Census Bureau will work with the states to conduct a thorough review of the program. The intent of this review, and the final report that results, is to provide guidance in planning the 2040 Census Redistricting Data Program.