The by-election in Caerphilly has drawn national attention, marking one of the most closely watched contests in Wales in recent years. The election was called following the passing of Hefin David, the long-serving Member of the Senedd for Caerphilly, whose death on 12 August 2025 prompted a significant moment of reflection across the political spectrum.
This by-election is widely viewed as one of the last contests to take place under the current electoral system before the forthcoming reforms to the Senedd take effect in 2026. These reforms, will introduce a larger Senedd and a new voting structure.
The campaign itself has been notably turbulent and high-profile, attracting considerable media coverage. With national issues such as the cost of living, public services, and climate policy dominating public debate, the Caerphilly by-election became a focal point for broader political tensions across Wales.
The Results
Lindsay Whittle of Plaid Cymru secured victory in the Caerphilly by-election with 47.4% of the vote, an increase of 19% compared with the party’s 2021 result. The outcome was stronger than expected, after polls in the run-up had indicated that Reform UK were leading.
Llŷr Powell of Reform UK finished second with 36%, a gain of 34.2% compared with 2021. Although the party did not take the seat, the result showed significant growth in support within the constituency.
Richard Tunnicliffe, WelshLabour, placed third, with its vote share falling from 46% in 2021 to 11%, a decrease of 34.9%. This marked the first time in over a century that Labour had not won in Caerphilly.
The Welsh Conservatives received 2% of the vote, down 15.3% compared with 2021.
Turnout reached a record 50.43%, making this the first Welsh Parliament by-election to exceed 50% turnout. The result represented a notable shift in Caerphilly’s voting patterns and a significant moment in the constituency’s electoral history.
Full Breakdown:
- (GAIN) Plaid Cymru – 47.4% (+19%)
- Reform UK – 36% (+34.2%)
- (LOSS) Labour – 11% (–34.9%)
- Conservative Party – 2% (–15.3%)
- Liberal Democrats – 1.5% (–1.2%)
- Green Party – 1.5% (+1.5%)
- UKIP – 0.2% (+0.2%)
- Gwlad – 0.3% (+0.3%)
The result is expected to shape both local and national discussion in the months ahead — offering an early indication of how political sentiment in Wales may be shifting ahead of the 2026 Senedd elections. As Wales prepares for its new political landscape, Caerphilly stands as a reminder of both the enduring and evolving nature of democracy in the nation.
Climate, Renewables and the Environment
Environmental and climate issues also featured prominently throughout the Caerphilly campaign. The proposed re-mining of spoil tips in Bedwas was one of the most debated topics, raised by the Coal Action Network, which asked candidates whether they supported the extraction of coal from former tips in the constituency and how such plans aligned with Wales’s wider climate commitments (Nation.Cymru). Several candidates voiced opposition to new coal extraction, arguing it would undermine progress towards net-zero targets.
Plaid Cymru’s campaign placed a strong emphasis on environmental priorities, pledging to tackle what it called the ‘climate change and biodiversity emergencies.’ The party outlined proposals for a Welsh-owned energy company to deliver 100 per cent renewable electricity, statutory nature-restoration targets by 2050, and a goal of zero emissions by 2035 (Plaid Cymru – Caerphilly Vision).
Green Party candidate Gareth Hughes also made climate and renewables central to his message, linking ‘green jobs,’ public transport improvements, and warm, energy-efficient homes to the local economy and well-being of Caerphilly residents (Caerphilly Observer).
At the same time, Caerphilly County Borough Council’s declaration of a Climate Emergency and its commitment to reach net-zero carbon by 2030 formed part of the local backdrop to the campaign. Some public commentary described these commitments as a positive step forward, while others questioned whether progress had been matched by delivery on the ground (Caerphilly Observer).
In short, while traditional political battlegrounds such as health, jobs, and public services dominated much of the conversation, the environment and renewable energy policy were far more visible in this by-election than in many previous contests in the area.