below. | nowrap | |- ! | William R. King | | Democratic-Republican | 1810 | | Incumbent resigned, effective November 4, 1816.New member elected before August 16, 1816.Democratic-Republican hold.Successor seated December 2, 1816.Winner later lost re-election to the next term, see below. | nowrap | |- ! | Richard Stanford | | Democratic-Republican | 1796 | | Incumbent died April 16, 1816.New member elected before August 22, 1816.Democratic-Republican hold.Successor seated December 2, 1816.Winner later lost re-election to the next term, see below. | nowrap | |- ! | Enos T. Throop | | Democratic-Republican | 1814 | | Incumbent resigned June 4, 1816 after losing re-election.New member elected August 27–29, 1816.Democratic-Republican hold.Successor seated December 3, 1816.Winner was not elected to the next term, see below. | nowrap | |- ! (Seat B) | William Pinkney | | Democratic-Republican | 17901791 1814 | | Incumbent resigned April 18, 1816 to become Minister to Russia.New member elected September 3, 1816.Democratic-Republican hold.Successor seated December 2, 1816.Successor was later re-elected to the next term, see below. | nowrap | |- ! | Alexander C. Hanson | | Federalist | 1812 | | Incumbent resigned after being elected to the Senate.New member elected October 6, 1816.Federalist-Republican hold.Successor seated December 2, 1816.Successor also elected the same day to the next term, see below. | nowrap | |- ! | John McLean | | Democratic-Republican | 1812 | | Incumbent resigned in April 1816 after being appointed to the Supreme Court of Ohio.New member elected October 8, 1816.Democratic-Republican hold.Successor seated December 2, 1816.Winner also elected, the same day, to the next term, see below. | nowrap | |- ! | Thomas Burnside | | Democratic-Republican | 1815 | | Incumbent resigned in April 1816 to accept judicial appointment.New member elected October 8, 1816.Democratic-Republican hold.Successor seated December 3, 1816.Successor also elected, the same day, to the next term, see below. | nowrap | |- ! | Thomas Gholson Jr. | | Democratic-Republican | 1808 | | Incumbent died July 4, 1816.New member elected October 10–28, 1816.Democratic-Republican hold.Successor seated December 4, 1816. | nowrap | |- ! | William Mayrant | | Democratic-Republican | 1814 | | Incumbent resigned October 21, 1816, having just lost re-election.New member elected November 25 & 26, 1816, who had also won the general election, see below.Democratic-Republican hold.Successor seated January 2, 1817. | nowrap | |- ! | Alfred Cuthbert | | Democratic-Republican