What is reapportionment?
Reapportionment divides the 435 voting House seats among the states after each census. It changes how many seats each state gets, not the total number of seats.
Article I, Section 2 of the Constitution apportions House seats among the states by population. It calls for a census every ten years.
Why does the House have 435 seats?
The Permanent Apportionment Act of 1929 fixed the House at 435 voting members. The law also created a procedure for reapportionment after each census. The Constitution does not set the current total of 435.
A vacant seat does not change a state's share of those 435 seats. The House membership guide explains the difference between apportioned seats and current voting members.
Can a state gain or lose seats?
Every state gets at least one House seat. After each census, a state can gain seats, lose seats, or keep the same number. Its share depends on its population compared with the other states.
A state can grow and still lose a seat if other states grow faster. Reapportionment does not change Senate seats. Every state still has two senators.
How does reapportionment differ from redistricting?
Reapportionment changes how many House seats each state gets. Redistricting then draws the district lines inside each state. States with one House seat have one statewide congressional district.
A state can redraw its districts even when its seat count stays the same. The redistricting guide explains how those boundaries affect which voters elect each representative.
Follow the votes behind your representation
Reapportionment sets your state's share of House seats. Your representative uses one of those seats to vote on bills. Follow those recorded votes to see which choices your members supported or opposed.
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