The Block Boundary Suggestion Project (BBSP) is Phase 1 of the Census Bureau's 2030 Redistricting Data Program, formally announced through a Federal Register notice on July 30, 2025. The purpose of the BBSP is to give 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 suggest that specific features be used as 2030 Census tabulation block boundaries, resulting in more meaningful block-level data for redistricting purposes. 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. The BBSP is conducted using GUPS Web, the Census Bureau's free web-based GIS application, and the deadline to submit 2030 BBSP updates is May 29, 2026.