This website provides information about the redistricting process in Pennsylvania, including information about the Legislative Reapportionment Commission created by the state Constitution, access to the geography and population data used for redistricting, interactive maps, and more.
Redistricting is the process by which the boundaries of elective districts are periodically redrawn to maintain equal representation on the basis of population.
Article 1, Section 2, of the United States Constitution requires that a Census be taken every 10 years for the purpose of apportioning the United States House of Representatives. Census results are used to determine the number of congressional seats apportioned to each state. After the 2000 federal Census, Pennsylvania had 19 members in the U.S. House of Representatives. Following the 2010 federal Census, Pennsylvania has 18 members of the U.S. House. More information on the Census is available at census.gov.
In addition to being used as a basis for apportioning seats in the U.S. House of Representatives, Census data is also used in Congressional and Legislative redistricting.
Public Law 94-171, enacted by Congress in December 1975, requires the Census Bureau to deliver redistricting data to state officials responsible for legislative redistricting no later than April 1, 2011. More information on the redistricting data program is available at www.census.gov/rdo/.
To contact the Legislative Reapportionment Commission, please visit our contact page.