The 1842–43 United States House of Representatives elections were held on various dates in various states between August 1, 1842 and November 8, 1843. Each state set its own date for its elections to the House of Representatives before the first session of the 28th United States Congress convened on December 4, 1843. The exception was Maryland, who held theirs so late that they ran into February 1844. These elections occurred during President John Tyler's term. The congressional reapportionment based on the 1840 United States census unusually decreased the number of House seats, from 242 down to 223.
The 1842 Newfoundland general election was held in 1842 to elect members of the 3rd General Assembly of Newfoundland in Newfoundland Colony. The elected assembly with 15 members and the appointed Legislative Council with 10 members were combined into a unicameral legislature.
The 1842–43 United States Senate elections were held on various dates in various states. As these U.S. Senate elections were prior to the ratification of the Seventeenth Amendment in 1913, senators were chosen by state legislatures. Senators were elected over a wide range of time throughout 1842 and 1843, and a seat may have been filled months late or remained vacant due to legislative deadlock. In these elections, terms were up for the senators in Class 3.
The members of the 3rd General Assembly of Newfoundland were elected in the Newfoundland general election held in 1842. The General Assembly sat from January 14, 1843 to 1848.
The 1843 Georgia gubernatorial election was held on October 2, 1843, to elect the governor of Georgia. Whig candidate George W. Crawford defeated the Democratic challenger Mark A. Cooper and was elected Governor.
The 1842 Massachusetts gubernatorial election consisted of an initial popular election held on November 14, 1842 that was followed by a legislative vote held on January 17, 1843. The ultimate task of electing the governor had been placed before the Massachusetts General Court because no candidate received the majority of the vote that was constitutionally required for a candidate to be elected through the popular election. Incumbent Whig Governor John Davis was defeated by Democratic nominee and former Governor Marcus Morton.
The 1842 New Hampshire gubernatorial election was held on March 8, 1842.
The 1843 Vermont gubernatorial election was held on September 5, 1843.
The 1845–46 Massachusetts gubernatorial election consisted of an initial popular election held on November 10, 1845 that was followed by a legislative vote held on January 12, 1846. The ultimate task of electing the governor had been placed before the Massachusetts General Court because no candidate received the majority of the vote required for a candidate to be elected through the popular election. Incumbent Whig Governor George N. Briggs defeated Democratic nominee Isaac Davis, Liberty Party nominee Samuel E. Sewall and Know Nothing nominee Henry Shaw.