Will there be exactly 7 UK parliamentary by-elections in 2026?

Recent UK parliamentary by-elections have been driven by Labour resignations amid internal leadership tensions, including Andrew Gwynne’s January 2026 exit for health reasons and Josh Simons stepping aside in May to enable Andy Burnham’s candidacy in Makerfield. Additional vacancies arose in June from SNP MPs resigning after the Scottish Parliament elections. With four contests already completed or underway by mid-year and the next general election not due until 2029, traders price in further triggers such as deaths, recalls, or party defections. This positions six total by-elections as the leading outcome, reflecting typical annual vacancy rates tempered by the compressed timeline remaining in 2026.

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