By-elections since the 2024 general election

Which parties have won the recent by-elections?

Former Labour Mayor of Greater Manchester Andy Burnham won the Makerfield by-election on 18 June 2026 with an increased vote share of 10 percentage points on the party’s 2024 general election win in the constituency. 

But Labour has lost two other by-elections since the 2024 general election. The Green Party won the Gorton and Denton by-election in February 2026, and Reform UK won the Runcorn and Helsby by-election in May 2025. 

Hannah Spencer from the Green Party won the Gorton and Denton seat with a majority of 4,402 votes, securing 41% of all the votes cast. Labour previously won the seat at the 2024 general election with 51% of the total vote and a majority of 13,413 votes. And in the Runcorn and Helsby by-election in May 2025, Sarah Pochin from the Reform party won the seat from the Labour party with just a six-vote majority. 

Two by-elections also took place in Scotland on 18 June 2026. The SNP held the Arbroath and Broughty Ferry seat with a majority of 4,961 votes, but lost the Aberdeen South constituency to the Conservatives who won 50% of the vote share. 

What triggered these by-elections?

The by-election in Makerfield was triggered when the former MP for Makerfield, Josh Simons stood down on 14 May 2026. Simons did so to allow Andy Burnham, then Mayor of Greater Manchester since 2017, to stand for election in the constituency in the hopes of opening a path for Burnham to become an MP and trigger a potential party leadership challenge. 

The two by-elections in Scotland in the constituencies of Aberdeen South and Arbroath and Broughty Ferry were triggered after two former SNP MPs – Stephen Flynn and Stephen Gethins – were elected to represent seats in the Scottish Parliament in May's devolved elections, vacating their Westminster seats.

The by-election in Gorton and Denton was triggered after the former Labour MP Andrew Gwynne resigned on medical grounds on 22 January 2026. Gwynne was an Independent MP at the time, having been suspended from the Labour Party in February 2025 following the revelation of inappropriate WhatsApp messages he had sent.

And in Runcorn and Helsby, Mike Amesbury, who was initially elected in 2024 as a Labour MP, stepped down on 17 March 2025, triggering a by-election in the constituency which was held on 1 May 2025. Amesbury resigned after pleading guilty to assault and was sentenced to 10 weeks in prison (the sentence was later suspended). Following the initial incident, Amesbury was suspended from the Labour Party and sat in the Commons as an independent MP. Amesbury has stated that he would have remained in place if he had not been given prison time. But by being sentenced to prison, one of the criteria for a recall petition had already been met, meaning that a by-election would have been triggered if more than 10% of constituency votes signed the petition.

How long does it take for a by-election to take place after an MP leaves office?

When an MP’s seat becomes vacant, the chief whip of the relevant political party (or another MP in the case of independents) moves a motion requesting that a new writ is issued for an election – this is known as ‘moving the Writ’. The Writ will typically be issued within three months of the seat becoming vacant and a by-election will take place between 21 and 27 days from this point. ⁷ UK Parliament, ‘By-elections’, www.parliament.uk/about/how/elections-and-voting/by-elections/

Do MPs continue to receive a salary in the lead-up to a by-election?

MPs continue to receive their salary until they step down. MPs are not employed in the normal way – they are paid by the Independent Parliamentary Standards Authority (IPSA), which has no discretion to withhold MPs pay except for any period where an MP has been suspended from the House. Equally, MPs have no choice but to be paid so long as they serve as an MP. ⁸ IPSA, ‘MPs’ pay facts’, 5 December 2022, www.theipsa.org.uk/news/mps-pay-facts

How do by-elections affect the amount of public money that parties receive?

By-elections do not impact the level of public funding that parties receive. The major source of public funding for political parties in opposition is Short Money. This is allocated to parties based only on a combination of the number of seats won and the number of votes received at the last general election – by-election results do not alter this calculation.

Are by-elections common?

By-elections were relatively common in the 2019–24 parliament with 23 being held. This was not an unusually large number by historical standards, but 11 by-elections were triggered due to misconduct, a significantly higher number than normal.