**Major Political Shifts in Wales Revealed by Decade of Polls**
A new analysis of every political poll in Wales over the past twelve years has spotlighted significant changes in the political fortunes of Plaid Cymru, Labour, and the emergent Reform UK. Since the inception of devolved government in 1999, Labour has consistently held power in Wales, often navigating a complex landscape by working alongside parties like Plaid Cymru and the Liberal Democrats, or operating as a minority government.
During these years, Welsh political dynamics at the Senedd have unfolded against a backdrop of shifting power in Westminster, with both Labour and the Conservatives alternating control and the rise and fall of UKIP, the Brexit Party, and more recently, Reform UK. The decline of the Liberal Democrat vote has further contributed to Wales’ evolving political scene. It is worth noting, however, that despite the turbulence, Labour has continued to return the highest number of Senedd members throughout this period.
Looking ahead, the 2026 Senedd election will mark a significant departure from tradition. Not only will there be an increase in the number of Senedd members from 60 to 96, but Wales will also see the introduction of new constituencies and changes to voting methods. Voters will no longer cast separate ballots for constituency and regional lists; instead, a single, streamlined process will be in place. All these changes have been designed to modernise and strengthen the electoral process, in line with similar efforts across the UK.
Political polling has been a regular feature of Welsh political life, with organisations such as YouGov conducting surveys into voter intentions for many years. The data, stretching back to 2013, illustrates the volatility of party support as Wales has grappled with national and global political upheavals. What is particularly remarkable is how parties have appeared, disappeared, or dramatically altered their electoral appeal over time. For example, UKIP made a notable impact around the time of the EU Referendum, but is no longer a force on the Welsh scene, while the former Brexit Party has morphed into Reform UK, whose influence is now surging.
Recent polling methodologies have also evolved. The latest poll in May 2025 employed an MRP (multi-level regression and post-stratification) model, which relies on a detailed statistical analysis of voter characteristics and uses local data to predict likely outcomes for different parties. This approach allows for nuanced predictions, taking into account the concentrations of various voter types across constituencies.
The May 2025 poll has proven to be particularly eye-opening, showing a dramatic reshuffling of political fortunes. For the first time, Plaid Cymru emerged as the projected largest party, signalling a potential turning point in Welsh self-governance. Reform UK surged into second place, leapfrogging Labour, who saw their support slump to just 18%—a record low since the dawn of devolution.
This polling shockwave has prompted introspection within Welsh Labour. First Minister Eluned Morgan acknowledged the gravity of the poll’s findings, describing it as a “serious wake-up call.” She stressed the urgent need for Labour, as well as the wider UK party, to reassess their policy delivery and reconnect with the priorities of Welsh voters. Her comments highlight a sense of urgency as Labour comes to terms with this unexpected wave of change.
Observers point out that the emerging trends reflect broader disillusionment with traditional parties and a renewed appetite for alternative political voices. The rise of Reform UK mirrors patterns seen elsewhere in the UK, while Plaid Cymru’s strong polling suggests an increasing appetite for home-grown solutions and a re-energised debate on Welsh autonomy.
As the 2026 Senedd election approaches, all eyes will be on how these evolving trends translate into actual parliamentary seats and political power. The shifting allegiances and rapidly changing political landscape promise an unpredictable and potentially watershed moment for Welsh democracy. The coming months will be critical as parties adapt their strategies, outreach, and messaging to remain relevant to an electorate in flux.