Proportional Representation Explained
List PR, STV, AMS, d’Hondt — all the systems that actually make seats match votes, and why 60% of Britons want one of them for Westminster.
What is Proportional Representation?
Proportional representation (PR) is any electoral system where a party’s share of seats in parliament closely matches its share of the national vote. If a party wins 30% of votes, it receives roughly 30% of seats. Under the UK’s current First Past the Post (FPTP) system, this relationship is routinely broken.
There is no single PR system — there are several different approaches, each with different trade-offs between proportionality, simplicity and the preservation of a local MP link. The UK already uses three different PR systems in devolved elections.
Key principle: Under PR, your vote has roughly equal weight regardless of where you live. Under FPTP, a vote in a safe seat is effectively wasted — it changes nothing. In 2024, an estimated 22 million UK votes were cast for losing candidates and had zero impact on the parliamentary result.
The Four Main PR Systems
Party List Proportional Representation
Voters choose a party. Seats are allocated in proportion to vote share. Candidates are drawn from a pre-ranked party list. The simplest and most common form of PR.
Used in: Germany (federal list seats), Netherlands, Spain, Israel, South Africa, most Scandinavian countries, European Parliament elections.
Pros: Highly proportional, simple to count. Cons: No direct local MP link; voters choose parties, not individuals.
Single Transferable Vote
Voters rank candidates in multi-member constituencies. Candidates reaching a quota are elected; surplus votes transfer down to lower preferences until all seats are filled.
Used in: Northern Ireland Assembly, Republic of Ireland general elections, Scottish local council elections, Australian Senate, Maltese general elections.
Pros: Voters express nuanced preferences; maintains local link. Cons: Counting is complex; large multi-member constituencies.
Additional Member System (Mixed-Member PR)
Voters get two votes: one for a local constituency MP (FPTP), one for a regional party list. The regional list seats correct the disproportionality of the constituency results, producing an overall proportional outcome.
Used in: Scotland (Holyrood), Wales (Senedd), London Assembly, Germany, New Zealand.
Pros: Keeps local MP link AND achieves proportionality. Cons: Creates two classes of representative (constituency vs list).
The d’Hondt Method
Not a full system but a mathematical formula for allocating seats within List PR or AMS. Each party’s vote total is repeatedly divided by the number of seats it has already won plus one. The party with the highest quotient wins the next seat. This repeats until all seats are distributed.
Used in: UK European Parliament elections (before Brexit), Scottish Parliament regional list seats, Welsh Senedd regional seats, London Assembly, over 30 countries worldwide.
Example: Party A has 40,000 votes. Party B has 25,000 votes. Seat 1 goes to A (40,000 ÷ 1 = 40,000). Seat 2 goes to B (25,000 ÷ 1 = 25,000 vs A’s 40,000 ÷ 2 = 20,000). Seat 3 goes to A again (40,000 ÷ 2 = 20,000 vs B’s 25,000 ÷ 2 = 12,500). And so on.
PR Already in the UK
The UK already runs four separate PR-based electoral systems alongside Westminster’s FPTP. This makes the debate about Westminster reform easier to ground in real experience.
Which Countries Use PR?
Over 80 countries use some form of proportional representation for their main legislative elections. The majority of European democracies use PR. The UK, USA, Canada and a handful of others remain FPTP outliers.
UK Public Polling on PR
Support for switching to a proportional system has grown markedly since the 2024 general election’s extreme outcome. Key polling findings:
of UK adults support a proportional voting system for Westminster (YouGov, 2025)
prefer to keep FPTP, with 15% undecided. Support for FPTP is declining.
of Lib Dem voters back PR. 68% of Green voters. Even 51% of Labour voters.
of Reform UK voters back PR, reflecting frustration at the party’s 2024 seat haul.
Arguments For and Against PR
Arguments For PR
- Every vote has roughly equal weight
- Parties represent their true voter share
- Reduces “wasted votes” and tactical voting
- Smaller parties can compete fairly
- Encourages coalition-building and compromise
- More women and diverse candidates elected in practice
Arguments Against PR
- Coalition governments can be unstable
- Voters elect parties, not individuals (list PR)
- Smaller parties gain disproportionate coalition leverage
- Long coalition negotiations delay government formation
- Local MP link may be weakened
- More complex to understand and administer
PR in Practice: Performance Across Democracies
One of the strongest arguments for evaluating PR is the performance record of the 80+ countries that use it. Critics predicted permanent instability; the evidence is more nuanced. Germany has used AMS since 1949 and has had mostly stable coalition governments with broadly consistent policy. New Zealand switched from FPTP to AMS in 1996 and by most measures experienced smooth democratic transitions.
The UK’s own PR experiments — in Scotland, Wales, London and Northern Ireland — provide the most direct evidence. All four jurisdictions have operated for over two decades without the democratic collapse that some predicted. Scotland’s Holyrood Parliament has produced both majority governments (SNP 2011) and minority/coalition arrangements, and has generally been judged to work effectively.
Note: Israel is often cited by FPTP defenders as a warning for PR. But Israel’s problems stem from an extremely low 3.25% electoral threshold combined with a single national constituency — features no serious UK PR proposal replicates. Germany and New Zealand demonstrate that well-designed AMS can deliver both proportionality and stable government.
The weight of international evidence suggests that the choice of PR system matters as much as the choice between PR and FPTP. A poorly designed PR system (Israel) can produce fragmentation. A well-designed one (Germany) can produce stable, representative government with broad voter satisfaction.
Frequently Asked Questions
What PR system does the Lib Dems want for the UK?
The Liberal Democrats formally support the Single Transferable Vote (STV) for Westminster elections. They argue STV keeps the link between voters and elected representatives while achieving proportionality. STV is used in Northern Ireland and the Republic of Ireland.
Would PR produce permanent coalition governments in the UK?
Probably more coalitions, yes — though not necessarily permanently unstable ones. Germany has operated stable coalition governments under AMS for decades. New Zealand switched to AMS in 1996 and has had functioning coalition governments consistently. Scotland’s AMS parliament has produced both majority and minority governments.
What would a 2024-style election look like under PR?
Under strict List PR, Labour would have won approximately 219 seats rather than 412. Reform UK would have won ~93 seats rather than 5. The Greens would have won ~43 seats rather than 4. No party would have a majority, and a coalition or confidence-and-supply arrangement would be required.
Is Scotland’s AMS system working?
By most measures, yes. Holyrood elections produce broadly proportional outcomes, with multiple parties represented. Scotland has had both majority governments (SNP 2011) and minority/coalition arrangements. The parliament consistently has more women MSPs than the House of Commons, partly due to parties’ use of list seats to improve gender balance.