Columns: District | Vacator | Reason for change | Successor | Date successor seated
Tennessee 1st | Vacant | Tennessee re-admitted into the Union | Nathaniel G. Taylor (U) | July 24, 1866 | Tennessee 2nd | Vacant | Tennessee re-admitted into the Union | Horace Maynard (UU) | July 24, 1866 | Tennessee 3rd | Vacant | Tennessee re-admitted into the Union | William B. Stokes (UU) | July 24, 1866 | Tennessee 4th | Vacant | Tennessee re-admitted into the Union | Edmund Cooper (U) | July 24, 1866 | Tennessee 5th | Vacant | Tennessee re-admitted into the Union | William B. Campbell (U) | July 24, 1866 | Tennessee 6th | Vacant | Tennessee re-admitted into the Union | Samuel M. Arnell (UU) | July 24, 1866 | Tennessee 7th | Vacant | Tennessee re-admitted into the Union | Isaac R. Hawkins (U) | July 24, 1866 | Tennessee 8th | Vacant | Tennessee re-admitted into the Union | John W. Leftwich (UU) | July 24, 1866 | New York 16th | Orlando Kellogg (R) | Died August 24, 1865 | Robert S. Hale (R) | December 3, 1866 | Pennsylvania 16th | Alexander H. Coffroth (D) | Lost contested election February 19, 1866 | William H. Koontz (R) | July 18, 1866 | Indiana 7th | Daniel W. Voorhees (D) | Lost contested election February 23, 1866 | Henry D. Washburn (R) | February 23, 1866 | New York 8th | James Brooks (D) | Lost contested election April 7, 1866 | William E. Dodge (R) | April 7, 1866 | New York 3rd | James Humphrey (R) | Died June 16, 1866 | John W. Hunter (D) | December 4, 1866 | Kentucky 3rd | Henry Grider (D) | Died September 7, 1866 | Elijah Hise (D) | December 3, 1866 | Pennsylvania 11th | Philip Johnson (D) | Died January 29, 1867 | Vacant | Not filled this term