UK parliamentary by-elections since 1945
This list notes the number of by-elections by session since 1945-46 together with a list of the the successful candidates in by-elections since 2005.

This Commons Library Briefing Paper sets out results of the by-elections held since the 2015 election. Currently there have been 10 by-elections, the latest two were held on 23 February 2017. Full details are presented in the associated PDF but an overview of the recent by-election results are shown below.
By-elections since the 2015 General Election (2 MB , PDF)
The election was called following the resignation of Tristram Hunt on 23 January 2017. Gareth Snell (Labour Party) was elected MP with a 2,620 (12.4%) majority.
Majority of winning candidate – 2,620 (12.4%)
Total poll – 21,170 (not including invalid votes)
Turnout – 38.1%
The election was called following the resignation of Jamieson Reed on 23 January 2017. Trudy Harrison (Conservatives) was elected MP with 44.3% of the vote (a 6.9% majority).
Majority of winning candidate – 2,147 (6.9%)
Total poll – 31,068 (not including invalid votes)
Turnout – 51.3%
The election was called following the resignation of Stephen Phillips on 4 November 2016. Caroline Johnson (Conservatives) was elected MP with 53.5% of the vote (a 40.0% majority).
Majority of winning candidate – 13,144 (40.0%)
Total poll – 32,834 (not including invalid votes)
Turnout – 37.0%
The election was called following the resignation of Zac Goldsmith on 25 October 2016. Sarah Olney (Liberal Democrats) was elected MP with 49.7% of the vote (a 4.5% majority). The writ was moved on 27 October.
Majority of winning candidate – 1,872 (4.2%)
Total poll – 41,283 (not including invalid votes)
Turnout – 53.4%
The election was called following the death of Jo Cox on 16 June 2016. Tracy Brabin has been elected (Labour Party) with 85.8% of the vote.
The Conservatives, Liberal Democrats, UKIP and Green Party decided not to stand at this election out of respect
Total poll – 20,393 (not including invalid votes)
Turnout – 25.6%
The election was called following the resignation of David Cameron on 12 September 2016. Robert Courts (Conservative Party) was elected MP with 45.0% of the vote (a 14.8% majority). The writ was moved on 15 September.
Majority of winning candidate – 5,702 (14.8%)
Total poll – 38,455 (not including invalid votes)
Turnout – 46.7%
The election was called when Sadiq Khan resigned as MP for Tooting on 9 May 2016 after London Mayor election on 5 May 2016. Rosena Allin-Khan (Labour Party) was elected MP with a 6,357 (19.9%) majority.
Majority of winning candidate – 6,357 (19.9%)
Total poll – 31,999 (not including invalid votes)
Turnout – 42.8%
The election was called after the resignation of Huw Irranca-Davies who switched from Ogmore Westminster MP to become the constituency’s Assembly Member (AM).
Majority of winning candidate – 8,358 (35.8%)
Total poll – 23,315 (not including invalid votes)
Turnout – 42.4%
The election was called after the death of Harry Harpham MP on 4 February 2016.
Majority of winning candidate – 9,590 (42.5%)
Total poll – 22,581 (not including invalid votes)
Turnout – 33.0%
The election was called after the death of Rt Hon. Michael Meacher MP on 21 October 2015.
Majority of winning candidate – 10,722 (38.7%)
Total poll – 27,706 (not including invalid votes)
Turnout – 40.1%
By-elections since the 2015 General Election (2 MB , PDF)
This list notes the number of by-elections by session since 1945-46 together with a list of the the successful candidates in by-elections since 2005.
A research briefing on the office and role of the Speaker of the House of Commons
This list reports all the women who have been elected as MPs to the House of Commons, for each election since 1918 and in the order they were sworn in.