List of Great Britain by-elections (1790–1800) By-elections 17th Parliament (1790–1796)

| Date_ | Constituency | c_u | Former_Incumbent | Winner | Cause_ |
|---|---|---|---|---|---|
| 14 June 1791 | Milborne Port | u | William Coles Medlycott | Richard Johnson | Resignation |
| 15 June 1791 | Edinburgh | u* | Henry Dundas | Henry Dundas | Home Secretary |
| 17 June 1791 | Dover | u* | Charles Small Pybus | Charles Small Pybus | Lord of the Admiralty |
| 17 June 1791 | Queenborough | u | Richard Hopkins | Richard Hopkins | Junior Lord of the Treasury |
| 17 June 1791 | Weymouth and Melcombe Regis | u | Thomas Jones | Sir James Johnstone | Resignation |
| 18 June 1791 | Haslemere | u* | Richard Penn | James Clarke Satterthwaite | Resignation |
| 20 June 1791 | Pontefract | u* | John Smyth | John Smyth | Lord of the Admiralty |