Voters in Wales will head to the polls on 7 May 2026 to elect their representatives to the Senedd, the Welsh parliament.
Two big changes are coming in this year’s elections. First, the number of constituencies is changing. Second, the electoral system is switching to a fully proportional system – so the number of seats a party wins will more closely reflect their share of the vote.
A lot of people are confused about the changes – so, in this post, we outline what is happening and what it means for elections to the Senedd.
In today’s system, Wales is made up of:
The 40 constituencies are each represented by one Member of the Senedd (MS). They are elected under first past the post (FPTP), where the candidate with the highest vote share wins.
The five regions are each represented by four regional MSs – totalling 20 regional MSs. They are elected under a proportional system.
That makes a total of 60 representatives in the Senedd.
Under the new system, the old constituencies and five regions will be scrapped. They will be replaced by 16 large constituencies.
Each of the 16 constituencies will be represented by six MSs. They will be elected by a proportional system.
This means there will be 96 Members of the Senedd.
The name of the new system is the closed proportional list system. It uses a mechanism called the D’Hondt formula, named after a 19th-century Belgian mathematician called Victor D'Hondt.
The D’Hondt formula is quite complicated!
It takes place in rounds, in which the number of votes a party (or independent candidate) gets is divided by the number of seats they have won, plus one.
For example, if Party X gets the most votes, they win the first round and get one seat. Imagine the number of votes they originally won was 300. In the second round, this number (300) is divided by the number of seats they have won (one), plus one. One plus one equals two, so the original number of votes (300) is divided by two in the second round. 300 divided by two equals 150. So, 150 votes are counted for Party X in round two. This is compared with the number of votes the other parties got, and whoever has the most wins the second round.
If Party X wins a second seat in a future round, the number of votes they won will be divided by three for the purposes of the round after that. And so on!
|
|
Party X |
Party Y |
Party Z |
Winner |
|
Round 1 |
300 |
280 |
120 |
Party X
1 seat + 1 = 2
300/2 = 150 in round 2 |
|
Round 2 |
150 |
280 |
120 |
Party Y
1 seat + 1 = 2
280/2 = 140 in round 2 |
|
Round 3 |
150 |
140 |
120 |
Party X
2 seats + 1 = 3
300/3 = 100 |
|
Round 4 |
100 |
140 |
120 |
Party Y
2 seats + 1 = 3
280/3 = 93 |
|
And so on… |
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|
|
|
Under this system, parties win a number of seats. Seats are then allocated to candidates based on a party list for that constituency, in which candidates are ranked in order. If a party has six candidates on their list and wins three seats, the top three candidates on their list are elected to the Senedd.
The new system is designed to make sure the number of seats a party ends up with reflects their vote share more closely than under the old system. Using the D’Hondt formula, a party that wins 50% of the votes in their constituency is likely to win three of the six seats.
Wales is part of the United Kingdom, and is therefore partly governed by the UK government. However, Wales has the power to make some of its own laws because of devolution, which was when the UK parliament passed powers to Northern Ireland, Scotland, Wales and parts of England. The Welsh parliament is called the Senedd.
On 7 May, Welsh voters will determine the makeup of the Senedd for the next four years, electing their new government. This may be a coalition government if no party wins an outright majority. If a party wins a majority of seats, that party will form the government.
The Welsh government has control over many aspects of policy in Wales, including:
Things like policing, justice and welfare are controlled by the UK government.
If you live in Wales and want to vote in the Senedd elections on 7 May, you will need to be registered to vote:
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