UK parliamentary by-elections since 1945
This list notes the number of by-elections by session since 1945-46 and also lists the successful candidate in by-elections since 2005.

This research paper provides the results of the 14 by-elections held during the 2005-10 Parliament.
By-elections 2005 - 2010 (107 KB , PDF)
Since 2005, 9 of the 14 by-elections have been won by the incumbent party. There has been a net gain to the Conservatives of two seats, after wins in Norwich North, and Crewe and Nantwich; a net gain of one seat to the Liberal Democrats, following a win in Dunfermline and West Fife; and a net gain of one seat to the SNP after victory in Glasgow East. All of these seats were previously held by Labour. Thus, after accounting for their win in Glasgow North East (previously held by former Speaker Michael Martin), Labour saw a net loss of three seats over this period.
By-elections 2005 - 2010 (107 KB , PDF)
This list notes the number of by-elections by session since 1945-46 and also lists the successful candidate in by-elections since 2005.
MPs that have announced they are standing down from the House of Commons ahead of the next general election.
This briefing explains the timetable for by-elections to the UK Parliament