Democracy and Boundary Commission Cymru publishes Final Determinations Report
The Democracy and Boundary Commission Cymru has today (11 March 2025) published its Final Determinations and confirmed the 16 constituencies that will be used to elect Members of the Senedd at the 2026 election.
The Senedd Cymru (Members and Elections) Act instructed the Commission to make recommendations for 16 constituencies to replace the current 40 constituencies and 5 regions.
These new constituencies will take effect automatically at the 2026 Senedd election, and 6 Members of the Senedd will be elected from each one, using the D’Hondt method previously used for the Senedd’s regional lists.
The Democracy and Boundary Commission Cymru had to create 16 constituencies by pairing Wales’ 32 UK parliamentary constituencies, ensuring that each constituency neighbours the one with which it is paired.
The 16 constituencies proposed by the Commission are:
Bangor Conwy Môn
Clwyd
Fflint Wrecsam
Gwynedd Maldwyn
Ceredigion Penfro
Sir Gaerfyrddin
Gŵyr Abertawe
Brycheiniog Tawe Nedd
Afan Ogwr Rhondda
Pontypridd Cynon Merthyr
Blaenau Gwent Caerffili Rhymni
Sir Fynwy Torfaen
Casnewydd Islwyn
Caerdydd Penarth
Caerdydd Ffynnon Taf
Pen-y-bont Bro Morgannwg
The Commission has made 2 changes to the paired constituencies since its Revised Proposals, with the creation of Caerdydd Penarth and Caerdydd Ffynnon Taf replacing the previously proposed De-ddwyrain Caerdydd Penarth, and Gogledd-orllewin Caerdydd constituencies.
The final configuration sees the parliamentary constituencies of Cardiff North and Cardiff East paired together, along with the pair of Cardiff West and Cardiff South and Penarth.
The Commission proposed this combination in its Initial Proposals report before changing it in its Revised Proposals. Representations received by the Commission during both consultations informed the Commission that there was greater public support for the combination made in its Final Determinations.
The Commission considers that constituencies are only “contiguous” or neighbouring if it is possible to travel throughout it without having to leave the constituency.
For example, the Commission did not consider Ynys Môn and Dwyfor Meirionnydd to be a viable pair since it is not possible to travel from one to the other by road without having to enter Bangor Aberconwy.
The Commission also considered local ties, such as shared history, the Welsh language, and socio-economic considerations in an attempt to create constituencies which feel as natural as possible to people across Wales.
The Commission does not however consider the impact of its proposals on future election results.
The Senedd Cymru (Members and Elections) Act 2024 states that “Each Senedd constituency must have a single name for the purposes of identifying the constituency in communication through Welsh and English, unless the Commission considers this would be unacceptable”.
The Commission has therefore assigned names to each constituency which it believes are acceptable and recognisable for people across Wales.
In many cases, such as “Clwyd”, no English translations of the place-names are in common use. In other cases, such as “Caerdydd Penarth”, the Commission takes the view that residents of Cardiff would recognise and understand the name Caerdydd and the area it refers to, making a translation of the name unnecessary.
During its Revised Proposals consultation period, the Commission did receive several comments on its proposed names and its naming conventions. While the Commission was open to ideas and suggestions regarding individual constituency names, it could not consider comments which proposed translations for all constituencies, or proposed entirely different naming conventions, due to the constraints of the act.
The Commission received over 4,000 responses during its consultation periods. This is, by a considerable margin, the highest number of responses received by either the Democracy and Boundary Commission Cymru, or its parliamentary equivalent, the Boundary Commission for Wales, during a review process.
Many of the responses received expressed general disagreement or agreement with the proposals, and many discussed matters outside of the scope of the Review.
However, the Commission also received many valuable suggestions from the public and stakeholders which have helped shape the Revised Proposals, and the Final Determinations.
The Commission’s Final Determinations report has been submitted to Welsh Government and the 16 constituencies determined by the Commission will take effect automatically at the 2026 Senedd election.
This brings the 2026 Review of Senedd constituencies to a close.
Commenting on the publication of the Final Determinations, Chief Executive of the Democracy and Boundary Commission Cymru, Shereen Williams MBE OStJ said:
“This review was the first Senedd constituency review undertaken by the Commission, and with a new electoral system, and an increase in the number of Members of the Senedd from 2026, the changes we’ve had to make have been very significant.
“The Commission would like to thank its partners in Welsh Government, the Senedd, local authorities, and the entire Welsh electoral community for their engagement with this review.
“Mostly however, the Commission wishes to thank the members of the public who have responded to its consultations in greater numbers than ever before.
“The debate over proposed pairs and names has been robust, but very constructive, and the constituencies recommended by the Commission have been significantly strengthened due to the public’s involvement in the process.
Constituencies for 2026 Senedd election confirmed