Columns: District | Vacator | Reason for change | Successor | Date successor seated
Connecticut At-large | Uriel Holmes (F) | Resigned sometime in 1818 | Sylvester Gilbert (DR) | Seated November 16, 1818 | North Carolina 11th | Daniel Forney (DR) | Resigned sometime in 1818 | William Davidson (F) | Seated December 2, 1818 | Massachusetts 20th | Albion K. Parris (DR | Resigned February 3, 1818 | Enoch Lincoln (DR) | Seated November 4, 1818 | Virginia 19th | Peterson Goodwyn (DR) | Died February 21, 1818 | John Pegram (DR) | Seated April 21, 1818 | Louisiana At-large | Thomas B. Robertson (DR) | Resigned April 20, 1818 | Thomas Butler (DR) | Seated November 16, 1818 | Pennsylvania 4th | Jacob Spangler (DR) | Resigned April 20, 1818 | Jacob Hostetter (DR) | Seated November 16, 1818 | Pennsylvania 6th | Samuel D. Ingham (DR) | Resigned July 6, 1818 | Samuel Moore (DR) | Seated October 13, 1818