PollCheck

UK Parliament By-Elections

Tracker, polling and constituency analysis for by-elections to the UK House of Commons.

Last updated 8 May 2026

Currently pending

Aberdeen South vacancy expected. Stephen Flynn (SNP) was elected to the Scottish Parliament on 7 May 2026 and has 49 days to resign his Westminster seat. A by-election will follow once the Speaker issues a writ. See Aberdeen South tracker ->

By-elections this Parliament

More for Gorton and Denton: Ward map explorer|Turnout map

Results table

Date Constituency Held by Winner Turnout
26 Feb 2026 Gorton and Denton Labour Green 47.5%

Frequently asked

How are UK by-elections triggered?

A by-election is held to fill a vacant seat in the House of Commons. Vacancies arise when an MP dies, resigns, is disqualified, or is expelled. The Speaker issues the writ for the by-election, usually within three months of the vacancy.

When is the next UK by-election?

There are no UK Parliament by-elections currently scheduled. This page is updated when a vacancy is announced and a writ is issued.

How does PollCheck forecast by-elections?

PollCheck combines national and regional polling, the constituency's 2024 General Election result, ward-level demographics, and constituency-specific polling where available. By-election models also account for typical mid-term swing patterns and protest-vote effects against the governing party.

How accurate are PollCheck by-election predictions?

By-elections are more volatile than General Elections because turnout is lower and local factors can dominate. PollCheck publishes a central projection alongside scenario ranges. For Gorton and Denton 2026 the central projection had Green at 31.6%, against an actual result of 40.6% - a reminder that ranges, not point estimates, are the right basis for planning.