Senedd: Revised constituency plans released by boundary commission

Revised plans to create 16 “super constituencies” for the 2026 Senedd election have been unveiled.

In September, the Democracy and Boundary Commission Cymru published its initial proposals to redraw Wales’ political map, replacing the current 40 constituencies and five regions.

In 2026, the Senedd will expand from 60 to 96 members and adopt a new electoral system, with the 32 constituencies used in July’s Westminster general election paired to create 16.

How will the 2026 Senedd election differ?

Currently, Wales uses an additional member system – a mix of proportional representation and the first-past-the-post system used in Westminster elections.

Forty constituency Senedd members are elected via first past the post and a further 20 are elected to represent five regions via party lists.

But from 2026 voters will receive one ballot rather than two, with first past the post scrapped and all members elected via a full form of proportional representation.

Wales will use “closed lists”, which will see people voting for parties rather than specific candidates, despite experts describing the new system as dangerous.

Political parties will decide the order of candidates on lists unlike under a flexible-list system or the single transferable vote which would give the electorate a say.

The D’Hondt method, a formula to apportion seats based on votes, will continue to be used over the Sainte-Lague system which would benefit smaller parties.

Following an initial consultation period, the commission has now published its updated plans.

In the initial proposals, the Caerphilly constituency was paired with the Blaenau Gwent and Rhymney seat, while Newport West and Islwyn joined with Newport East. These remain unchanged in the revised plans.

One thing that has changed in the proposals is the name of the proposed new constituencies using Welsh instead of English.

The 16 constituencies proposed by the commission are:

Bangor Conwy Môn
Clwyd
Fflint Wrecsam
Gwynedd Maldwyn
Ceredigion Penfro
Sir Gâr
Gorllewin Abertawe Gŵyr (Swansea West Gower)
De Powys Tawe Nedd (South Powys Tawe Neath)
Afan Ogwr Rhondda
Merthyr Cynon Taf
Blaenau Gwent Caerffili Rhymni
Mynwy Torfaen
Casnewydd Islwyn
De-ddwyrain Caerdydd Penarth (Cardiff South-east Penarth)
Gogledd-orllewin Caerdydd (Cardiff North-west)
Pen-y-bont Bro Morgannwg

The commission said it received 3,700 responses following the release of its initial proposals, including suggestions which it says have helped shape the revised proposals.

It said the responses have led it to “change the proposed configuration of constituencies in the Cardiff area”, as well to make “significant changes to its proposed names”.

When deciding which constituencies to pair, the commission looked at local ties, such as shared history, the Welsh language, and socio-economics.

But the commission said it does not consider the impact of its proposals on future election results when making its decisions.

‘Significant step’

The commission’s chief executive, Shereen Williams MBE OStJ, said the proposals “represent a significant step on the journey to creating Wales’s new constituencies”.

The consultation period for the latest proposals closes on January 13, with the commission publishing its final decisions at the end of March.

Ms Williams continued: “The rules in place for this review mean that certain proposals can’t be changed, but following the feedback we received from the public, we have made significant adjustments to the proposed names, as well as changing the configuration of constituencies in the Cardiff area.

“The commission remains open to making further changes, depending on the representations we receive during this consultation, so we urge everyone to share their views before January 13.”

Wojtek Gurak

Revised plans shaking up the Welsh political map released

‘Significant step’

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