Brecon and Radnorshire () is a constituency of the Senedd. It elects one Member of the Senedd by the first past the post method of election. Also, however, it is one of eight constituencies in the Mid and West Wales electoral region, which elects four additional members, in addition to eight constituency members, to produce a degree of proportional representation for the region as a whole. It has been represented since May 2021 by James Evans, who elected as a Conservative, but had the whip removed in January 2026 before joining Reform UK in February 2026.
The constituency was created for the first election to the Assembly, in 1999, with the name and boundaries of the Brecon and Radnorshire Westminster constituency. It is entirely within the preserved county of Powys, and one of three Powys constituencies. Also, it is one of eight constituencies in the Mid and West Wales electoral region.
The other Powys constituencies are Montgomeryshire and Clwyd South. Montgomeryshire is also entirely within the preserved county of Powys, and within the Mid and West Wales region. Clwyd South is partly, and mostly, a Clwyd constituency, and within the North Wales electoral region.
The region consists of the eight constituencies of Brecon and Radnorshire, Carmarthen East and Dinefwr, Carmarthen West and South Pembrokeshire, Ceredigion, Llanelli, Meirionnydd Nant Conwy, Montgomeryshire and Preseli Pembrokeshire.
Constituency boundaries changed from the 2007 Assembly election, as did regional boundaries. Brecon and Radnorshire remained a Powys constituency, however, and one of eight constituencies in the Mid and West Wales electoral region.
Brecon and Radnorshire is one of two constituencies covering Powys, both entirely within the preserved county, and both within the Mid and West Wales region. The other Powys constituency is Montgomeryshire.
The Mid and West Wales region consists of the constituencies of Brecon and Radnorshire, Carmarthen East and Dinefwr, Carmarthen West and South Pembrokeshire, Ceredigion, Dwyfor Meirionnydd, Llanelli, Montgomeryshire and Preseli Pembrokeshire.
For Westminster purposes, the same new constituency boundaries became effective for the 2010 United Kingdom general election and ceased to be used following the 2023 review of Westminster constituencies.
In general elections for the Senedd, each voter has two votes. The first vote may be used to vote for a candidate to become the Member of the Senedd for the voter's constituency, elected by the first past the post system. The second vote may be used to vote for a regional closed party list of candidates. Additional member seats are allocated from the lists by the d'Hondt method, with constituency results being taken into account in the allocation.
Regional ballots rejected: 311
2003 Electorate: 53,739<br> Regional ballots rejected: 282