In the 230 plus years that Congress has been in existence since March 4, 1789, we have had 11,037 people serve in the House of Representatives, and 1,983 people serve in the US Senate.
10,360 members served only in the House of Representatives, while 1,306 members served only in the US Senate, and 677 members have served in both bodies of Congress.
29 members of the House of Representatives have served 40 or more years, with John Dingell of Michigan serving the longest, 59 years from 1955 to 2015.
16 Women in the House of Representatives have served 25 or more years, with Marcy Kaptur of Ohio, having served 36 plus years since 1983, the longest of any woman, and still serving, with Nancy Pelosi, the House Speaker, being the third longest serving at nearly 32 years and counting from California since 1987.
25 US Senators have served 35 and a half years or more, with Robert Byrd of West Virginia serving nearly 51 and a half years from 1959 to 2010. Daniel Inouye of Hawaii served nearly 50 years from 1963 to 2012, while Strom Thurmond of South Carolina served 47 and a half years and was past age 100 when he left the Senate. Ted Kennedy of Massachusetts served 46 years and more than 9 months from 1962 to 2009. Vermont Senator Patrick Leahy, still in the Senate, is 5th longest serving at 44 plus years since 1975.