Apportionment is the process of dividing the 435 memberships, or seats, in the U.S. House of Representatives among the 50 states. At the conclusion of each decennial census, the results are used to calculate the number of House memberships to which each state is entitled. This map shows the changes to the number of Congressional seats for each state between apportionment based on the 2010 Census and apportionment based on the 2020 Census.
2020 Census Apportionment Results
Congressional seats were apportioned among the 50 states based on the 2020 Census population counts. Apportionment results from 1790 to 2020 are also shown.
Historical Apportionment Data Map (Interactive)
This interactive tool enables users to view more than 10 decades of apportionment and population data.
Information about congressional apportionment for the current and past Decennial Censuses.
Source and References
2020 Decennial Census