2025 Caerphilly by-election

The 2025 Caerphilly by-election was held on 23 October 2025 to elect the new member of the Senedd (MS) for the Senedd constituency of Caerphilly following the death of Hefin David on 12 August 2025. Former Senedd member Lindsay Whittle of Plaid Cymru won the by-election with 47% of the vote, ending more than a hundred years of Labour representation in UK Parliament and Senedd elections in Caerphilly, and outperforming expectations of a closer race between Plaid Cymru and Reform UK. Voter turnout was 50.43%, the highest ever for a Senedd by-election.

Source: Wikipedia — 2025 Caerphilly by-election (CC BY-SA 4.0)