By-elections since the 2024 general election
Details of UK parliamentary by-elections since the 2024 general election are provided below.
| Constituency | Reason for by-election | Date of by-election | New Member |
| Runcorn and Helsby | Resignation of Mike Amesbury, 17 March 2025 | 1 May 2025 | Sarah Pochin (Reform UK gain) |