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The 192nd General Court of the Commonwealth of Massachusetts

US Census Data for Redistricting

US Census Data for Redistricting

Public Law (P.L.) 94-171, enacted in 1975, directs the U.S. Census Bureau to make special preparations to provide redistricting data needed by the 50 states. It specifies that within a year following Census Day (by April 1, 2021), the Census Bureau must send the governor and legislature in each state the data they need to redraw districts for the United States Congress and state legislature. The objective of the Census 2000 Redistricting Data Program was to produce the data that the Census Bureau provides to states to meet the requirements of P.L. 94-171.

To meet this legal requirement, the Census Bureau set up a program that affords state officials an opportunity before each decennial census to define the small areas for which they wish to receive census population totals for redistricting purposes. Officials then can receive data for voting districts (e.g., election precincts, wards, state representative and senate districts) in addition to standard census geographic areas, such as counties, cities, census tracts, and blocks. State participation in defining areas is voluntary and nonpartisan.

The Census Bureau has delayed the release of this data until September 30, 2021.

US Census Key Dates


April 1, 2020 was Census Day. When completing the census, people marked where they were living—and included everyone living in their home—as of April 1, 2020.

July 16 - October 15 2020: Census takers interviewed homes that had not responded to the 2020 Census to make sure everyone was counted.

October 15, 2020: Self-response data collection ended. The Census Bureau reports that over 99.9% of households had self-responded or been counted by census takers.

2021 (Adjusted due to COVID-19)

April 30, 2021:  The Census Bureau will deliver population counts used for congressional apportionment to the president as required by law.

September 30, 2021:  The Census Bureau will send redistricting counts to the states. This information is used to redraw legislative districts based on population changes.