Two years
The Texas House of Representatives is composed of 150 members, each elected for a two-year term. A member of the house must be a citizen of the United States, must be a qualified elector of the state, and must be at least 21 years old.  Members of the U.S. House of Representatives are elected by their constituents to represent their districts in Congress. Elections are held on the Tuesday after the first Monday in November of even-numbered years. Representatives, the title given to Members of the U.S. House of Representatives, are elected to serve a two year term. Becoming a Representative. The United States Constitution outlines the only requirements for candidates to the U.S. House of Representatives. To be eligible, a candidate must be at least 25 years old, have lived in the United States for at least seven years, and live in the state they would represent. Article I, Section 2 of the U.S. Constitution states, The House of Representatives shall chuse their Speaker and other Officers.. Although the Constitution does not require the Speaker to be a Member of the House, all Speakers have been Members. Members-elect of the U.S. House of Representatives typically take the Oath of Office on the House Floor on the first day of a new Congress, immediately after the Speaker of the House has been elected and sworn in. Each state has equal representation in the Senate. Two senators are elected by the voters to represent each state. Senators are elected for six year terms, however elections for a state's senators are not held during the same election years. In other words, no two senators are elected in a state at the same time. In order to be qualified to run for senator, a candidate must be at least 30 years old. He or she must have been a citizen of the United States for at least 9 years, and must live in the state he or she represents. Report Abuse. All 435 Representatives are up for re-election every two years. Even though you didn't ask, Senators serve 6 year terms, and 1/3 of the Senators are up for re-election every two years. Thus only 1/3 of the Senate seats are up for grabs every two years, but all seats in the House are up for grabs. Barbara E from Houston Texas · 7 years ago. All 435 seats in the House of Representatives are up for re-election every two years during even numbered years. Members serve two-year terms. Senators serve six-year terms. Approximately one third of the Senate is up for re-election every two years. There are 535 members of Congress 100 Senators and 435 Representatives. All states have two Senators while population determines representation in the House. The Commonwealth has 9 members of the House of Representatives. Representatives are elected by the voters in that congressional district for a term of two years. Requirements for representatives are different than those of the senators. Representatives must be 25 years of age or older. They must have been citizens of the United States for at least 7 years, and must live in the state they will represent. In other words, no two senators are elected in a state at the same time. In order to be qualified to run for senator, a candidate must be at least 30 years old. He or she must have been a citizen of the United States for at least 9 years, and must live in the state he or she represents. “The House of Representatives shall be composed of Members chosen every second Year by the People of the several States, and the Electors in each State shall have the Qualifications requisite for Electors of the most numerous Branch of the State Legislature.”. — U.S. Constitution, Article I, section 2, clause 1. 
http://www.house.state.tx.us/resources/frequently-asked-questions/ http://kids.clerk.house.gov/high-school/lesson.html?intID=35 http://clerk.house.gov/member_info/memberfaq.aspx http://www.studyzone.org/testprep/ss5/b/electsennrepl.cfm https://answers.yahoo.com/question/index?qid=20080812184632AAupIhg http://capuano.house.gov/services/faq.shtml http://www.studyzone.org/testprep/ss5/b/electsennrepl.cfm http://history.house.gov/Institution/Origins-Development/Biennial-Elections/
how often are representatives to be elected