31st United States Congress

The apportionment of seats in this House of Representatives was based on the 1840 United States census.

During this Congress, two House seats were added for the new state of California.

Senators were elected by the state legislatures every two years, with one-third beginning new six-year terms with each Congress.

Preceding the names in the list below are Senate class numbers, which indicate the cycle of their election.

The names of members of the House of Representatives are preceded by their district numbers.

President of the Senate
Millard Fillmore
Senators' party membership by state at the opening of the 31st Congress in March 1849. The green stripes represent Free Soil. California's senators were not seated until September 10, 1850.
2 Democrats
1 Democrat and 1 Whig
2 Whigs
House seats by party holding plurality in state
80+% to 100% Democratic
Up to 60% Whig
60+% to 80% Democratic
60+% to 80% Whig
Up to 60% Democratic
80+% to 100% Whig
33% Free Soil Party
Speaker Howell Cobb