Key facts
435
Voting members of the US House
House.gov
10 years
Time between census counts used to divide House seats
Art. I, § 2, cl. 3
10 states
States that changed congressional maps between censuses since summer 2025, as of July 14, 2026
NCSL
You live in several districts at once
Your address places you in a US House DistrictAn area set up for a purpose, such as the area whose voters elect one representative or the area a school district or other special district serves.Read more in the glossary, in state legislative districts and often in local ones, such as a city WardA division of a city or borough used to organize elections and, in some places, to elect local officials.Read more in the glossary or a School districtA local government that runs public schools in a set area. In some places, public schools are run instead by a city, county, town or state agency.Read more in the glossary. These lines do not follow ZIP codes. One ZIP code can overlap more than one congressional district, so official lookup tools may ask for your street address.
Step 1: Dividing the seats
The ConstitutionThe highest law of a country or state. It sets up the government, divides its powers and protects rights, and the United States and each state have their own.Read more in the glossary requires a census every 10 years. For the 2020 census, the Census Bureau counted all residents, citizens and noncitizens alike. It must give the state totals to the president by December 31 of the census year. The 435 House seats are then divided by a formula called the method of equal proportions, and every state gets at least 1. After the 2020 census, 6 states gained seats and 7 lost one.
Step 2: Drawing the lines
Each state with more than 1 seat must use single-member districts, with 1 representative per district. In most states, the legislature draws the congressional map. As of November 2026, NCSL lists 10 states where a commission has the main responsibility for congressional maps, and 15 for state legislative maps. Courts can also order new maps.
The legal limits
Districts must have roughly equal populations, a rule known as one person, one vote, and states may not discriminate by race in drawing them. Section 2 of the Voting Rights Act also applies. In Louisiana v. Callais, decided April 29, 2026, the Supreme Court ruled 6–3 on how Section 2 applies to maps. It held that a map violates Section 2 only when the evidence strongly suggests the state drew it on purpose to give minority voters less opportunity because of their race. In Rucho v. Common Cause (2019), the Supreme Court ruled 5–4 that federal courts cannot decide partisan gerrymandering claims, meaning claims that a map was drawn to favor a party. State courts can still apply state laws to those claims.
Maps can change between censuses
States usually redraw once a decade, but some have redrawn sooner. Since summer 2025, 10 states have changed their congressional maps, according to an NCSL tracker updated July 14, 2026. The changes came through legislatures, a redistricting commission, a ballot measure and court orders.
Representatives shall be apportioned among the several States according to their respective numbers, counting the whole number of persons in each State, excluding Indians not taxed.
Questions people ask
Who draws congressional districts?
What is gerrymandering?
How often are districts redrawn?
Sources
Checked November 4, 2026. Primary sources first, then official records, then nonpartisan research.
How these facts were checked: our promise. Every substantive fix is listed on the corrections page.
Keep going
Offices
What is the difference between a senator and a representative?
Each state has 2 US senators who serve 6-year terms, while 435 representatives serve 2-year terms. Learn how the House and Senate differ.
Elections
When are US elections held?
The US House is elected every 2 years, the president every 4 and senators for 6-year terms. See how federal, state and local election dates fit together.
Power
How can you tell who holds power in government?
To find who decides an issue, ask who proposes it, who approves it, who carries it out and who can review it. Examples show how the answer changes.