There were special elections to the U.S. House of Representatives in 1921.
|-! | Fred Blackmon| | 1910| | Incumbent died February 8, 1921.
New member elected June 7, 1921.
Democratic hold.| nowrap |
|-! | Samuel M. Taylor| | 1912| | Incumbent died September 13, 1921.
New member elected October 25, 1921.
Democratic hold.| nowrap |
|-! | colspan=3 | Vacant| | Representative-elect Charles F. Van de Water (R) died November 20, 1920.
New member elected February 15, 1921.
Republican hold.| nowrap |
|-! | James W. Good| | 1908| | Incumbent resigned June 15, 1921.
New member elected.
Republican hold.| nowrap |
|-! | Willfred W. Lufkin| | 1917| | Incumbent resigned June 30, 1921.
New member elected.
Republican hold.| nowrap |
|-! | William H. Frankhauser| | 1920| | Incumbent died May 9, 1921.
New member elected June 28, 1921.
Republican hold.| nowrap |
|-! | Mahlon Morris Garland| | 1914| | Incumbent died November 19, 1921.
New member elected September 20, 1921.
Republican hold.| nowrap | |}