Labour has fallen further behind in the latest Senedd voting intention poll, with Plaid Cymru now holding a clear lead over Reform UK, according to new research from YouGov/Cardiff University.
The poll shows Labour’s projected Senedd vote share has dropped to just 10 percent, placing it level with the Conservatives and well behind both Plaid Cymru and Reform UK. Plaid Cymru leads the field on 33 percent, while Reform UK sits close behind on 30 percent, unchanged since the September ITV Wales YouGov poll.
The findings highlight a significant shift in Welsh political behaviour. Rather than voters moving between left and right wing parties, researchers say the change is driven by consolidation within political identities. Welsh identifying progressive voters are increasingly rallying behind Plaid Cymru, moving away from Labour, while British identifying conservative voters are consolidating behind Reform UK at the expense of the Conservatives.
Researchers describe this as a sign of distinct Welsh political dynamics. While Reform UK’s rise mirrors trends seen elsewhere in Britain, Plaid Cymru’s growth is viewed as a uniquely Welsh development. Among former Labour voters who have switched to Plaid Cymru, 40 percent say their main reason is the party’s stance on standing up for Wales, an issue traditionally associated with Welsh Labour.
The full Senedd voting intention figures, excluding non voters and those who answered don’t know, are as follows.
- Plaid Cymru 33%
- Reform UK 30%
- Labour 10%
- Conservatives 10%
- Green Party 9%
- Liberal Democrats 6%
- Other parties 3%
The poll was conducted among 1,891 respondents, with data weighted using population based methods.
Based on these figures, Dr Jac Larner’s seat projection suggests a dramatic reshaping of the Senedd. Plaid Cymru would emerge as the largest party with 39 seats, followed by Reform UK on 34. Labour would be reduced to just 10 seats, with the Conservatives on 6. The Greens are projected to win 4 seats, while the Liberal Democrats would take 3.
If replicated at an election, the results would mark one of Labour’s weakest performances in the history of devolution and underline the growing fragmentation of Welsh politics.
