Plaid Cymru storms ahead as shock Senedd poll predicts political earthquake in Wales
The YouGov poll for ITV Cymru Wales and Cardiff University shows Plaid climbing to 37% of the vote — fourteen points clear of Reform UK — in a result that would trigger the biggest political shake‑up since devolution began in 1999.
Reform drops to 23%, the Greens leap to a record 13%, and Labour slumps to just 10%, its lowest Senedd rating ever recorded. The Conservatives also sit at 10%, leaving Wales’ two traditional governing parties tied for fourth place.
Under Wales’ new 96‑member Senedd, the figures would translate to Plaid winning 45 seats, just four short of an outright majority. Reform would take 23, the Greens 11, Labour eight and the Conservatives six.
Labour collapse deepens as Greens surge
The poll confirms a dramatic realignment in Welsh politics. Labour, which has dominated every Welsh election since 1922, now risks losing power for the first time in the history of devolution.
The Greens, meanwhile, record their strongest ever Welsh performance, overtaking Labour and the Conservatives for the first time.
Reform UK, which had been neck‑and‑neck with Plaid throughout 2025, sees its support fall sharply.
Senedd voting intention (YouGov / ITV Cymru Wales)
Fieldwork: 5–12 January 2026 • Wales • % of vote
Plaid Cymru
37%
Reform UK
23%
Green
13%
Labour
10%
Conservative
10%
Lib Dem
5%
Other
2%
Source: YouGov poll for ITV Cymru Wales and Cardiff University, January 2026.
Young voters break decisively with Labour as Greens and Plaid dominate
The raw YouGov data reveals a dramatic generational divide that cuts to the heart of Wales’ political realignment. Among 16 to 24‑year‑olds, the Greens now lead the field on 43%, with Plaid Cymru close behind on 42% — a combined 85% share that leaves the traditional parties almost nowhere.
Reform UK records just 6% among young voters, while Labour slumps to 4%, its weakest demographic performance in the entire poll.
The picture among older voters is far more fragmented. In the 65+ group, Plaid Cymru leads on 29%, with Reform UK close behind on 28%. The Conservatives remain competitive at 19%, while Labour manages 13% and the Greens fall to 4%.
The figures underline the scale of Labour’s challenge. The party that once dominated every age group in Wales is now squeezed from both sides — losing younger voters to Plaid and the Greens, and older voters to Reform and the Conservatives.
They also highlight the depth of Plaid Cymru’s surge. The party is now ahead among older voters and competitive among the youngest, a rare position in Welsh politics and one that strengthens its path to becoming the largest party in May.
Senedd voting intention — Age 16–24
YouGov / ITV Cymru Wales • January 2026
Conservative 0%
Labour 4%
Lib Dem 5%
Plaid Cymru 42%
Reform UK 6%
Green 43%
Other 0%
Senedd voting intention — Age 25–49
YouGov / ITV Cymru Wales • January 2026
Conservative 6%
Labour 7%
Lib Dem 5%
Plaid Cymru 47%
Reform UK 15%
Green 17%
Other 3%
Senedd voting intention — Age 50–64
YouGov / ITV Cymru Wales • January 2026
Conservative 7%
Labour 12%
Lib Dem 7%
Plaid Cymru 32%
Reform UK 33%
Green 7%
Other 2%
Senedd voting intention — Age 65+
YouGov / ITV Cymru Wales • January 2026
Conservative 19%
Labour 13%
Lib Dem 4%
Plaid Cymru 29%
Reform UK 28%
Green 4%
Other 2%
“A substantial shift” says leading academic
Dr Jac Larner, Cardiff University’s Welsh Governance Centre, said: This poll shows a stark contrast to previous polling, with a substantial 14‑point gap between Plaid Cymru and Reform UK in Senedd voting intention. While any single poll should come with a health warning, it continues broader trends in Welsh polling, where Plaid have enjoyed a modest boost and the Greens have surged.
He said the gains for Plaid and the Greens appear to be coming from previously undecided voters, and that Plaid is now seen by a majority of respondents as the party best placed to challenge Reform.
Parties react as campaign pressure intensifies
Plaid Cymru said the poll confirms the election is now a straight fight between them and Reform, claiming more voters are backing the party’s “positive vision for Wales”.
Welsh Labour said it was focused on “helping make people’s lives better”, while accusing Plaid of returning to its independence plans without explaining how they would be funded.
Westminster shock as Plaid overtakes Reform
The poll also shows Plaid now leading Westminster voting intention in Wales, rising to 29% and overtaking Reform on 25%. Labour collapses to 13%, with the Conservatives and Greens tied on 12%.
The shift follows Plaid’s by‑election victory in Caerphilly last autumn and rising approval for party leader Rhun ap Iorwerth.
Wales heading for its most unpredictable election
With four months to go, the poll suggests Wales could be on the verge of a political realignment not seen in a generation. A Plaid Cymru First Minister is now a realistic prospect, with the party potentially able to govern with only Green support.
Reform UK remains a serious contender for official opposition, while Labour faces the possibility of losing power for the first time since devolution.
The poll surveyed 1,220 adults for Senedd voting intention and 1,205 adults for Westminster voting intention between 5 and 12 January.
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