Electoral Systems used in the UK

Electoral systems determine how votes cast by citizens are converted into seats in a legislature or council.

Across the United Kingdom, several electoral systems operate concurrently across national, devolved, mayoral, and local elections.

This reflects distinct democratic priorities, ranging from strong single-party government to local representation, voter choice, and proportional outcomes.

1. First Past the Post (FPTP)

Explanation

First Past the Post is a single-member plurality voting system.

The geographic area is divided into single-member constituencies or wards.

Electors mark a single cross next to one candidate on the ballot paper.

The candidate who secures the highest number of votes in that constituency wins the seat, regardless of whether they achieve an absolute majority (over 50%) of the total vote cast.

Types of Election Used In:

UK General Elections: Electing Members of Parliament (MPs) to the House of Commons.

English Local Council Elections: Electing local councillors in single-member wards across England.

Directly Elected Mayors in England: Electing combined authority metro mayors (for example, Greater Manchester, West Midlands) and local council authority mayors (such as the Mayor of London).

Analysis & Evaluation

FPTP prioritises a clear constituency link and aims to produce stable, single-party majority governments.

However, it operates on a “winner-takes-all” basis, leading to high levels of disproportionality between a party’s nationwide vote share and its resulting percentage of parliamentary seats.

It heavily penalises parties whose support is spread evenly across the nation while rewarding parties with concentrated regional voting bases.

Strengths / Advantages:

Simplicity: Straightforward for voters to mark a single cross and easy for election officials to count quickly.

Strong Constituency Link: Every citizen has one single local MP or councillor directly accountable to their geographical area.

Decisive Governance: Frequently delivers single-party majority governments with clear mandates to pass legislation without complex coalition bargaining.

Barrier to Extremism: Prevents fringe or radical parties from winning seats unless their support is highly concentrated in specific geographic pockets.

Weaknesses / Disadvantages:

High Disproportionality: Nationwide seat totals often bear little relation to overall vote percentages.

Wasted Votes & Safe Seats: Votes cast for losing candidates, or surplus votes for a winning candidate beyond what was needed, have no impact on the overall result, creating safe seats where one party dominates perpetually.

Tactical Voting: Forces voters to vote defensively for a second-choice party to stop their least favourite candidate from winning, rather than expressing a true preference.

Minority Rule: Governs the country through executive majorities backed by only a minority of the total electorate.

Recent Uses and Outcomes

UK General Election (4 July 2024): The Labour Party secured a parliamentary majority of 412 seats (63.2% of all seats) despite winning 33.7% of the popular vote.
In contrast, smaller parties with geographically widespread support faced severe penalties: Reform UK and the Green Party collectively earned over 23% of the total vote but won only 2.7% of the seats (18 seats combined). 58% of all votes cast were non-effective (wasted).
English Mayoral Elections (May 2024): Following the Elections Act 2022, elections for English combined authority mayors and the Mayor of London switched from the Supplementary Vote (SV) to FPTP. In the London Mayoral election, Sadiq Khan was re-elected under simple FPTP plurality, securing 43.8% of the vote without secondary preference transfers.

2. Additional Member System (AMS)

Explanation

The Additional Member System is a hybrid electoral system that combines First Past the Post with Proportional Representation. Voters cast two separate votes on their ballot paper:

Constituency Vote: Elects a local representative using standard FPTP.
Regional Vote: Elects additional representatives from a party list to achieve overall proportionality across a region.

Regional list seats are allocated using a mathematical formula (the D’Hondt method) that compensates parties that were under-represented in the constituency results relative to their regional vote share.

Types of Election Used In:

Scottish Parliament Elections: Electing Members of the Scottish Parliament (MSPs) to Holyrood.
London Assembly Elections: Electing Assembly Members to scrutinise the Mayor of London.

(Note: Wales historically used AMS for Senedd Cymru elections from 1999 until 2021, but transitioned to a Closed List system in 2026).

Analysis & Evaluation

AMS balances direct local accountability with proportional representation. It retains a dedicated constituency representative while ensuring that smaller parties with substantial regional backing can win seats. However, it creates two distinct classes of representative: constituency members (accountable to a local electorate) and regional list members (accountable primarily to their party hierarchy).

Strengths / Advantages:

Proportionality with Local Ties: Corrects the unfairness of FPTP while retaining a single local constituency representative for every elector.
Voter Split-Ticket Choice: Allows electors to vote for a local candidate from one party while casting their regional vote for a different party.
Reduces Wasted Votes: Ensures that votes cast for smaller parties on the regional list count directly toward electing representatives.
Prevents Single-Party Dominance: Encourages consensus politics, coalition building, and compromise in legislative bodies.

Weaknesses / Disadvantages:

Two-Tier System: Creates tension between constituency representatives (who hold a direct local mandate) and list representatives (who have no specific local boundaries).
Party Hierarchy Control: Political party leaders control candidate ordering on regional lists, giving party elites significant power over who gets elected.
Strategic Gaming: Parties can attempt to game the system (for example, establishing separate list parties) to maximise regional top-up seats.
Counting Complexity: The D’Hondt allocation calculation is less intuitive to the general public than basic plurality counting.

Recent Uses and Outcomes

Scottish Parliament Election (7 May 2026): The Scottish National Party (SNP) won 58 seats, remaining the largest party at Holyrood but falling seven seats short of an overall majority. The D’Hondt regional calculation compensated opposition parties, resulting in 17 seats for Labour, 17 for Reform UK, 15 for the Greens, 12 for the Conservatives, and 10 for the Liberal Democrats.
WHAT IF . . . Scotland had used FPTP instead of AMS in 2026?
London Assembly Elections (May 2024): Used alongside the mayoral contest to elect 25 assembly members (14 single-member constituency seats and 11 London-wide list seats).

3. Single Transferable Vote (STV)

Explanation

The Single Transferable Vote is a preferential voting system used in multi-member constituencies. Voters rank candidates in numerical order of preference (1 for first choice, 2 for second choice, and so on).

To secure election, a candidate must reach a specific vote threshold known as the Droop Quota:

If a candidate exceeds the quota on first-preference votes, they are elected, and their surplus votes are transferred to remaining candidates based on voters’ secondary preferences. If no candidate meets the quota, the lowest-ranking candidate is eliminated, and their votes are redistributed until all seats are filled.

Types of Election Used In:

Northern Ireland Assembly Elections: Electing Members of the Legislative Assembly (MLAs) to Stormont.
Local Government Elections in Scotland: Electing councillors across multi-member wards in all 32 Scottish local authorities.
Local Government Elections in Northern Ireland: Electing councillors across multi-member district electoral areas.

Analysis & Evaluation

STV is widely regarded as a voter-centric system because it maximises individual choice. Voters can rank candidates from the same party or across different parties. It produces proportional outcomes and virtually eliminates wasted votes through preference transfers. Its main drawbacks are the complexity of the counting process and the large size of multi-member boundaries, which can dilute the personal constituency connection.

Strengths / Advantages:

Maximum Voter Choice: Electors can choose between multiple candidates from the same party, rank candidates across party lines, or vote for independents.
High Proportionality without Party Lists: Achieves proportional results without granting central party bosses control over candidate rankings.
Eliminates Safe Seats: Candidates within the same party must compete against one another for voter preferences, driving active local campaigning.
Cross-Community Consensus: Encourages candidates to appeal to secondary preferences outside their immediate core base, promoting moderation.

Weaknesses / Disadvantages:

Complex Counting Process: Involves multiple rounds of quota calculations and fractional vote transfers, often taking days to yield final results.
Diluted Local Accountability: Multi-member constituencies are geographically large, meaning voters have several representatives rather than one dedicated individual MP.
Potential for Intra-Party Friction: Candidates from the same political party are forced to compete against each other for first-preference votes.
Coalition Instability: Regularly yields highly fragmented assemblies that require complex, protracted coalition negotiations.

Recent Uses and Outcomes

Northern Ireland Assembly Election (5 May 2022): 90 Members (MLAs) were elected across 18 multi-member constituencies (5 seats per constituency). Sinn Féin won 27 seats with 29.0% of first-preference votes, becoming the largest party. The cross-community Alliance Party achieved major gains by attracting preference transfers from both nationalist and unionist voters, rising to 17 seats despite winning 13.5% of first-preference votes.
Scottish Local Government Elections (May 2022) & Northern Ireland Local Council Elections (May 2023): Used across multi-member wards to elect local councillors. In Scotland, STV regularly results in balanced local councils that require formal multi-party coalitions or administration agreements to govern.

4. Closed Proportional List System

Explanation

In a Closed Proportional List system, multi-member electoral regions elect multiple representatives.

Political parties publish an ordered list of candidates prior to polling day. Electors cast a single vote for a political party rather than an individual candidate.

Seats are distributed among parties in proportion to their overall regional vote share using mathematical formulas like D’Hondt. Successful candidates enter office strictly in the pre-ordered sequence established by the party leadership.

Types of Election Used In:

Senedd Cymru / Welsh Parliament Elections: Electing Members of the Senedd (MSPs) across six-member constituencies in Wales.
UK European Parliament Elections (Historically): Used across 12 UK regional constituencies to elect Members of the European Parliament (MEPs) prior to Brexit.

Analysis & Evaluation

This system offers near-perfect party proportionality, matching a party’s total vote share directly to its share of seats. It simplifies the voting process for electors.

However, it places power in the hands of party officials who control list rankings. Voters cannot select individual candidates or alter list orders, removing direct candidate-level accountability.

Strengths / Advantages:

Exact Party Proportionality: Ensures that a party’s total percentage of seats closely reflects its overall percentage of the popular vote.
Simplicity for the Elector: Highly straightforward on polling day; voters simply choose a single party logo or name.
Fairness to Small Parties: Enables smaller parties crossing regional vote thresholds to win representation proportional to their true public support.
Promotes Demographic Diversity: Party leaderships can structure their pre-ordered candidate lists to guarantee gender balance or minority representation.

Weaknesses / Disadvantages:

Severed Local Connection: Voters elect a national or regional party slate, losing any single local MP accountable to their specific town or district.
Absolute Party Control: Candidates are beholden to party leaders who determine list placement, rather than to the electorate. Unpopular individuals can be shielded near the top of lists.
No Individual Candidate Choice: Electors cannot split their vote or select a preferred individual candidate within a party list.
Disproportionate Coalition Power: Small kingmaker parties can hold outsize leverage over major parties during post-election cabinet formation.

Recent Uses and Outcomes

Senedd Cymru / Welsh Parliament Election (7 May 2026): Under the Senedd Cymru (Members and Elections) Act 2024, Wales officially replaced AMS with a Closed List Proportional System across 16 six-member constituencies. Plaid Cymru became the largest party with 43 seats on 35.4% of the vote, Reform UK entered the Senedd with 34 seats (29.3%), Welsh Labour fell to 9 seats (11.1%), the Conservatives won 7 seats, the Greens won 2 seats, and the Liberal Democrats won 1 seat.
WHAT IF . . . Wales had used FPTP instead of Closed List in 2026?
UK European Parliament Elections (May 2019): Historically used across 12 UK regional constituencies prior to the UK’s withdrawal from the European Union.

Detailed Comparative Matrix

Electoral System	Primary UK Application	Key Strengths / Advantages	Key Weaknesses / Disadvantages	Impact on Governance & Electorate
First Past the Post (FPTP)	– UK Parliament – English Local Councils – English Combined Authority Mayors	– Simple and clear: Extremely easy to vote (single cross) and fast to count. – Direct local link: Every constituent has one single MP or councillor accountable to their area. – Decisive majorities: Often yields single-party governments with strong legislative mandates. – Extremism filter: Blocks radical parties without concentrated local voting bases.	– Extreme disproportionality: Nationwide seat share frequently distorts popular vote share. – High vote wastage: Over 50% of votes cast can be non-effective (wasted). – Safe seat apathy: Reduces voter turnout in areas where one party dominates perpetually. – Encourages tactical voting: Drives voters to vote defensively rather than express true preference.	– Favours stable single-party executives over compromise. – Creates significant legislative majorities on minority vote shares. – Concentrates political campaign resources entirely on a small number of swing seats.
Additional Member System (AMS)	– Scottish Parliament – London Assembly	– Proportional yet local: Combines local constituency MPs with regional top-up seats. – Split-ticket voting: Gives voters two choices (one local person, one regional party). – Reduces wasted votes: Secondary regional votes actively shape final parliamentary totals. – Cross-party consensus: Discourages executive dominance and encourages inter-party compromise.	– Two-tier representatives: Risk of friction between constituency MPs (local mandate) and list MPs (no local mandate). – Party list control: Party bosses control regional list rankings and candidate priority. – Complex calculation: Uses the D’Hondt formula, which is less transparent to ordinary voters. – Gaming risks: Parties can set up separate “dummy” lists to bypass top-up penalties.	– Frequently produces minority governments or formal coalitions. – Delivers broader public representation while keeping a identifiable local representative. – Encourages negotiated policymaking and legislative scrutiny.
Single Transferable Vote (STV)	– Northern Ireland Assembly – Scottish Local Councils – Northern Ireland Local Councils	– Maximum voter empowerment: Electors rank candidates numerically () across or within parties. – High proportionality without rigid lists: Reaches fair seat distribution without giving power to central party bosses. – No safe seats: Candidates from the same party must compete against each other for preferences. – Cross-community incentive: Candidates seek lower-order preferences from rival communities.	– Complex counting procedure: Involves multiple rounds of quota calculations and vote transfers. – Diluted local link: Multi-member constituencies mean voters share several representatives. – Intra-party rivalry: Competing party candidates may target each other rather than opponents. – Fragmented assemblies: Can cause protracted coalition negotiations or deadlock.	– Highly responsive to individual voter preferences. – Virtually eliminates wasted votes through automated transfer mechanisms. – Requires power-sharing executive agreements in deeply divided polities.
Closed Proportional List	– Senedd Cymru (Welsh Parliament)	– Exact party proportionality: Matches regional seat percentage directly to total party vote percentage. – Maximum ballot simplicity: Voters make a single straightforward mark for their chosen party. – Fairness to small parties: Ensures any party reaching a regional threshold gets equal seat representation. – Balanced slates: Parties can structure lists to ensure demographic or gender balance.	– Severed constituency link: Removes direct single-member local representative accountability. – Total party patronage: Party leaders hold absolute power over who tops candidate lists. – Zero individual choice: Electors cannot vote for an individual candidate or alter list ordering. – Outsize coalition leverage: Small fringe parties can hold excessive power during cabinet formation.	– Maximises party-level democratic equity. – Elevates party platforms over personal candidate popularity. – Encourages coalition building and inter-party cooperation in legislative chambers.

Evaluation and Conclusion

The choice of electoral system across the United Kingdom reflects a fundamental conflict between competing democratic priorities:

Governance vs. Fair Representation: First Past the Post prioritises executive strength, speed of decision-making, and direct local accountability at the expense of fairness and voter equity.

Proportionality vs. Candidate Choice: Hybrid systems like AMS attempt to bridge the gap between FPTP and PR, whereas STV prioritises voter empowerment and proportionality without granting central party bosses control over lists.

Party Control vs. Local Link: Closed Proportional List systems maximise party fairness and simplify voting, but complete list closure severs individual constituent representation and concentrates authority inside central party headquarters.

The divergence across Westminster, Holyrood, Cardiff Bay, Stormont, and local government demonstrates that no single voting model satisfies all democratic requirements.

Each system offers distinct structural strengths and trade-offs depending on whether the priority is single-party stability, local representation, proportional outcome, or voter choice.

WHAT IF . . . Scotland had used FPTP instead of AMS in 2026?

WHAT IF . . . Wales had used FPTP instead of Closed List in 2026?