2, 1965 |- | | nowrap| Clarence J. Brown (R) | style="font-size:80%" | Died August 23, 1965 | nowrap | Bud Brown (R) | November 2, 1965 |- | | nowrap| James Roosevelt (D) | style="font-size:80%" | Resigned September 30, 1965, to become the US Representative to the United Nations Economic and Social Council | nowrap | Thomas M. Rees (D) | December 15, 1965 |- | | nowrap| Herbert Covington Bonner (D) | style="font-size:80%" | Died November 7, 1965 | nowrap | Walter B. Jones Sr. (D) | February 5, 1966 |- | | nowrap| John Lindsay (R) | style="font-size:80%" | Resigned December 31, 1965, after being elected Mayor of New York City | nowrap | Theodore R. Kupferman (R) | February 8, 1966 |- | | nowrap| Oren Harris (D) | style="font-size:80%" | Resigned February 3, 1966, to become judge of the US Court of the Eastern and Western Districts of Arkansas | nowrap | David Pryor (D) | November 8, 1966 |- | | nowrap| Albert Thomas (D) | style="font-size:80%" | Died February 15, 1966 | nowrap | Lera Millard Thomas (D) | March 26, 1966 |- | | nowrap| John F. Baldwin Jr. (R) | style="font-size:80%" | Died March 9, 1966 | nowrap | Jerome Waldie (D) | June 7, 1966 |- | | nowrap| Robert P. Griffin (R) | style="font-size:80%" | Resigned May 10, 1966, after being appointed to the U.S. Senate | nowrap | Guy Vander Jagt (R) | November 8, 1966 |- | | nowrap| Ralph Julian Rivers (D) | style="font-size:80%" | Resigned December 30, 1966 | rowspan=10 |Vacant | rowspan=10 |Not filled this term |- | | nowrap| Winfield K. Denton (D) | style="font-size:80%" | Resigned December 30, 1966 |- | | nowrap| Ralph Harvey (R) | style="font-size:80%" | Resigned December 30, 1966 |- | | nowrap| Leo W. O'Brien (D) | style="font-size:80%" | Resigned December 30, 1966 |- | | nowrap| Harold D. Cooley (D) | style="font-size:80%" | Resigned December 30, 1966 |- | | nowrap| Robert T. Secrest (D) | style="font-size:80%" | Resigned December 30, 1966 |- | | nowrap| Paul B. Dague (R) | style="font-size:80%" | Resigned December 30, 1966 |- | | nowrap| John C. Kunkel (R) | style="font-size:80%" | Resigned December 30, 1966 |- | | nowrap| Tom J. Murray (D) | style="font-size:80%" | Resigned December 30, 1966 |- | | nowrap| Clark W. Thompson (D) |