Wales is heading for a political earthquake on May 7, according to the most detailed poll yet published ahead of the Senedd election.
Research group More in Common has released its first MRP — a sophisticated seat-by-seat modelling technique that goes far beyond standard polling — and the findings represent a dramatic moment in Welsh politics.
Plaid Cymru is projected to win 30 seats, making it the largest party in the 96-seat Senedd for the first time since devolution in 1999. Reform UK is close behind on 28, with Labour falling to just 24 — a historic collapse for a party that has governed Wales continuously for 27 years.
The Conservatives are forecast to hold seven seats, the Greens four, and the Liberal Democrats three.
Luke Tryl, Executive Director of More in Common UK, said the scale of the shift was extraordinary. “Looking at Wales today, it’s hard to believe that the 2024 general election was less than two years ago — the political map has changed so dramatically since Labour won decisively in Wales,” he said.
“Having governed in Wales for 28 years, Labour is set to be pushed into third place — and for the first time we could see Wales led by a non-Labour First Minister. Plaid Cymru are the clear beneficiaries of a country ready for change, and could be on course to lead a Welsh government for the first time.”
The polling, carried out between January 30 and April 10 with a sample of 2,519 Welsh adults aged 16 and over, shows implied vote shares of 25% each for Plaid Cymru and Reform UK, 21% for Labour, 11% for the Conservatives, 10% for the Greens, and 7% for the Liberal Democrats. Independents and other candidates are polling at under 2% in most constituencies and are not projected to win any seats under this model.
It is the more conservative of two recent MRPs: a JL Partners poll for the Telegraph, published last week, put Plaid on 37 seats — a more commanding lead still.
What it means for your area — and who you’ll be voting for
Wales is using a closed list proportional representation system for the first time in this election, meaning voters choose a party rather than an individual candidate. Seats are then allocated in order from each party’s published list. That means we can say not just which parties are likely to win seats — but exactly who those winners are likely to be.
Gŵyr Abertawe (Swansea)
The Swansea constituency is projected as a dead heat, with each of the top three parties taking two seats apiece on virtually identical vote shares.
Reform UK lead on 25%, ahead of Plaid Cymru on 24% and Labour on 22%. Both Reform UK candidates Francesca O’Brien — the Mumbles ward councillor who defected from the Welsh Conservatives to Reform UK last August, having previously served as the party’s deputy leader in Swansea — and Steven Rodaway would be elected. Labour’s two seats would go to former MS Mike Hedges and Swansea council leader Rob Stewart. Plaid Cymru would return Gwyn Williams and Safa Elhassan.
The Greens are on 10% and the Conservatives also on 10%, with neither projected to win a seat here.
Sir Gaerfyrddin (Carmarthenshire)
Plaid Cymru are dominant in Carmarthenshire, polling at 37% — well ahead of Reform UK on 26% and Labour on 21%.
That translates to three seats for Plaid: Cefin Campbell, Nerys Evans, and former party leader Adam Price would all be returned. Reform UK’s Gareth Beer and Carmelo Colasanto would take two seats, and Labour’s Calum Higgins would hold the sixth and final place.
Brycheiniog Tawe Nedd (Neath Port Talbot/Brecon)
This is the most fragmented constituency in our area, with six different parties projected to win one seat each — one of the most competitive contests in all of Wales.
Reform UK lead on 27%, with Labour on 21%, Plaid on 19%, the Liberal Democrats on 13%, the Conservatives on 11%, and the Greens on 10%. On those figures the elected members would be: Reform UK’s James Oswald David Evans and Iain Charles McIntosh; Labour’s Dr Mahaboob Basha; Plaid Cymru’s Sioned Williams MS; Liberal Democrats’ Jane Dodds MS; and Conservative Tyler John Chambers.
Pen-y-bont Bro Morgannwg (Bridgend)
Bridgend mirrors the Swansea picture — a three-way tie with two seats each for Reform UK, Plaid Cymru, and Labour. Reform poll 27%, Plaid 24%, and Labour 24%.
Sarah Cooper-Lesadd and Gareth Thomas would be elected for Reform; Mark Hooper and Sarah Rees for Plaid; and Sarah Murphy and Huw John David for Labour.
Afan Ogwr Rhondda (Neath Port Talbot/Rhondda)
This is Reform UK’s strongest projected result in our area. They lead on 36% — ahead of Plaid Cymru on 25% and Labour on 21% — and are projected to win three of the six seats.
Benjamin Hodge McKenna, Steve Bayliss, and Darren James would all be elected for Reform. Plaid’s Sera Evans and Alun Cox would take two seats, with Labour’s Huw Irranca-Davies — currently serving as Deputy First Minister — narrowly holding on with the sixth seat.
Ceredigion Penfro (Pembrokeshire)
Plaid Cymru dominate Pembrokeshire and Ceredigion with 38% of the vote, projected to win three seats. The current Llywydd (Speaker) Elin Jones would top their list, followed by Kerry Elizabeth Ferguson and Anna Nicholl.
Reform UK’s Susan Claire Archibald would take one seat on 20%, and former Conservative Senedd leader Paul Windsor Davies would be returned for the Conservatives on 14%.
In a notable shift from some earlier polls, First Minister Eluned Morgan MS would retain her seat as Labour’s sole representative in the constituency on 14%. Previous MRP modelling had placed her seat at serious risk — this poll suggests she survives, though the margin remains tight.
A volatile result
More in Common highlight that the outcome remains fluid. Labour and Reform hold or contest the final seat in a large number of constituencies, meaning minor swings in support on polling day could shift the overall totals significantly either way.
What is beyond doubt is that Wales is heading for a result that would have been unthinkable even five years ago — a Senedd led by Plaid Cymru for the first time, with the party that barely existed in Welsh politics two years ago threatening to become the dominant force from Swansea to the Valleys.
More in Common’s full MRP data is available at moreincommon.org.uk. The Senedd election takes place on Thursday, May 7, 2026.
