Proportional Representation (PR) is the idea that seats in parliament should closely match votes cast in an election. A system that’s perfectly proportional would mean that if a political party received one third of the votes, they could then expect one third of the seats in parliament.
At present, in UK general elections, we don’t use a proportional system for voting MPs into the House of Commons. Instead, we use the First Past the Post (FPTP) system, where the number of MPs a party gets is often very different to the party’s share of votes.
There are a variety of possible PR voting systems including the Single Transferable Vote (STV), which is our preferred electoral system. What could voters expect to see if PR – specifically, the Single Transferable Vote – is introduced in the UK?
Parliament would be more proportional
With proportional representation our parliament would look different because parties’ seat share would much more closely match their vote share.
In the case of the 2024 UK General Election, which was the most disproportional in history, 57.8% of voters were unrepresented as they voted for a candidate that didn’t get elected.
This happened because of the FPTP system where a successful candidate can win by as little as one vote, and where geography plays a decisive role: if votes happen to be spread out over a geographical area rather than being highly concentrated, then chances are that many of those votes will be wasted, resulting in little parliamentary representation
Under PR, you could expect to see parliaments which more accurately reflect votes cast in a general election. For a visual illustration, our modelling in the wake of the 2024 General Election paints a picture of how parliament might have looked if we had used different proportional electoral systems, including STV.
Our ballot papers would be different
If Britain had proportional representation, the way we vote, and the ways those votes are counted, would be somewhat different.
For the most part, the process of voting would be similar to what we all know and expect: going to the polling station on election day and casting your vote with a pencil on a piece of paper.
However, voting would be slightly different under different types of proportional system. For example, under STV, rather than placing an ‘X’ next to one candidate, you would numerically rank candidates in order of preference. You would be able to rank as many or as few candidates as you like.
There would then be a number of rounds of vote counting in order to identify the winners for each constituency.
Constituencies would have more than one representative
If the UK had proportional representation, our constituencies might look different.
Assuming that STV is the system being used, the UK would have somewhat larger constituencies. Where we might currently have three constituencies each electing one MP, there may be cases where there’s one large constituency which elects three MPs.
Ireland and Malta both use STV for their national elections. In Ireland, constituencies have from 3 to 5 seats. In Malta, constituencies have 5 seats.
The key takeaway is that under a proportional system, voters would be represented by more than one MP, making it much more likely that that they will be represented by at least one candidate or party that they voted for.
Coalition or single-party majority? It depends on the voters
Some people associate PR with coalitions, rather than single-party majority governments. It’s true that PR can lead to coalitions, but it’s not true that that’s an inevitability.
In Scotland, where a form of PR called the Additional Member System (AMS) is used, the SNP formed a majority in 2011.
New Zealand also uses AMS, and in 2020 the Labour Party secured enough votes to form a single-party majority. They opted instead for a ‘cooperation’ agreement with the Green party, favouring a more collaborative form of government.
Ultimately, though, it depends on the voters. Under PR, when you do end up with a single-party majority, it’s because a majority of people, or close to a majority, voted for that party, rather than the FPTP system unfairly delivering a majority without the numbers to back it up.
On the other hand, if no party is popular enough to rule alone, then that’s because they weren’t popular with enough voters.
Either way, coalition or majority, the result is because of the will of the people, not an unfair quirk of the system.
Countries around the world
Hypotheticals aside, many countries around the world do use PR. In fact, it’s the most popular form of democracy in the world.
Looking at the systems of other countries can provide some insight into how proportional representation can and does work in practice.
For example, as mentioned above, Ireland uses the Single Transferable Vote. In 2020, we spoke to Irish voters about their experiences of voting under STV. They told us that the system means that ‘your vote matters, no matter where you live in the country’, and that they felt that political parties were able to work together rather than lean into divisions.
It’s time for fair votes for our general elections
The exact mechanics of Proportional Representation, if it’s implemented in Britain, will require careful thought and planning. That’s true of any political reform.
But with the British public seeing disproportional election results time and time again, and with polling in December 2024 showing 44% of the public want to change to a proportional voting system, one thing is clear: it’s time to scrap first past the post and adopt PR.
You can strengthen our campaign for Proportional Representation
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