Below are lists of Plaid Cymru target seats showing which constituencies can be most easily won from an opposing party relative to the latest elections.
Below is the list of Plaid Cymru target seats for the 2025 general election. The list is ordered from the smallest to the largest swing needed for the seat to change hands.
View Plaid Cymru held marginal seats vulnerable at the next general election.
(order by percentage majority)
| Rank | Constituency | Region | Majority | Swing Needed | |
|---|---|---|---|---|---|
| 1. | Ynys Mon | Wales | 2,541 | 3.48% | |
| 2. | Llanelli | Wales | 9,077 | 11.87% | |
| 3. | Caerphilly | Wales | 11,594 | 14.45% | |
| 4. | Neath | Wales | 11,425 | 15.75% | |
| 5. | Pontypridd | Wales | 12,391 | 16.65% | |
| 6. | Rhondda | Wales | 12,046 | 20.32% | |
| 7. | Ogmore | Wales | 14,683 | 20.74% | |
| 8. | Cynon Valley | Wales | 12,971 | 21.45% | |
| 9. | Cardiff West | Wales | 20,044 | 21.70% | |
| 10. | Blaenau Gwent | Wales | 13,140 | 21.74% | |
| 11. | Islwyn | Wales | 13,070 | 22.14% | |
| 12. | Merthyr Tydfil and Rhymney | Wales | 14,467 | 22.43% | |
| 13. | Aberavon | Wales | 14,297 | 22.62% | |
| 14. | Swansea East | Wales | 15,500 | 23.08% | |
| 15. | Swansea West | Wales | 16,509 | 23.42% | |
| 16. | Clwyd West | Wales | 16,496 | 24.25% | |
| 17. | Cardiff South and Penarth | Wales | 24,996 | 24.71% | |
| 18. | Carmarthen West and Pembrokeshire South | Wales | 18,550 | 25.66% | |
| 19. | Torfaen | Wales | 14,105 | 27.88% | |
| 20. | Monmouth | Wales | 24,978 | 29.86% | |
View Plaid Cymru held marginal seats vulnerable at the next general election.
Below is the list of Plaid Cymru target seats for the 2026 Senedd election. The list is ordered from the smallest to the largest swing needed for the seat to change hands.
View Plaid Cymru held marginal seats vulnerable at the next Senedd election.
(order by percentage majority)
| Rank | Constituency | Region | Majority | Swing Needed | |
|---|---|---|---|---|---|
| 1. | Aberconwy | North Wales | 3,336 | 7.08% | |
| 2. | Caerphilly | South Wales East | 5,078 | 8.78% | |
| 3. | Llanelli | Mid and West Wales | 5,675 | 9.39% | |
| 4. | Neath | South Wales West | 5,221 | 9.47% | |
| 5. | Pontypridd | South Wales Central | 5,328 | 9.67% | |
| 6. | Wrexham | North Wales | 3,620 | 10.04% | |
| 7. | Clwyd West | North Wales | 6,230 | 10.98% | |
| 8. | Carmarthen West and Pembrokeshire South | Mid and West Wales | 4,625 | 11.65% | |
| 9. | Rhondda | South Wales Central | 5,497 | 11.72% | |
| 10. | Islwyn | South Wales East | 6,032 | 12.32% | |
| 11. | Aberavon | South Wales West | 5,745 | 12.96% | |
| 12. | Clwyd South | North Wales | 6,354 | 14.22% | |
| 13. | Swansea West | South Wales West | 7,216 | 15.04% | |
| 14. | Montgomeryshire | Mid and West Wales | 7,528 | 15.06% | |
| 15. | Preseli Pembrokeshire | Mid and West Wales | 6,160 | 15.10% | |
| 16. | Blaenau Gwent | South Wales East | 6,638 | 15.94% | |
| 17. | Cardiff West | South Wales Central | 11,768 | 16.11% | |
| 18. | Ogmore | South Wales West | 8,165 | 16.67% | |
| 19. | Cardiff Central | South Wales Central | 9,630 | 16.88% | |
| 20. | Bridgend | South Wales West | 9,297 | 17.76% | |
| 21. | Cardiff South and Penarth | South Wales Central | 13,196 | 18.13% | |
| 22. | Cynon Valley | South Wales Central | 7,468 | 18.20% | |
| 23. | Torfaen | South Wales East | 9,008 | 18.80% | |
| 24. | Gower | South Wales West | 11,685 | 20.78% | |
| 25. | Brecon and Radnorshire | Mid and West Wales | 10,666 | 21.32% | |
View Plaid Cymru held marginal seats vulnerable at the next Senedd election.
