Tactical voting is the act of casting a vote for a candidate who is not the voter’s first preference, in order to prevent an even less desirable candidate from winning. It is a pragmatic calculation, where a voter opts for a “lesser evil” to block a “greater evil.”

Ultimately, tactical voters fear an idealistic vote might gift an election to their least preferred candidate.

The practice is a direct consequence of the UK’s first past the post (FPTP) electoral system used for general elections – as a candidate only needs a plurality of votes (one more than any other candidate) to win a constituency.

Tactical voting has become a significant feature of British politics, and was a major factor in the outcome of the 2024 general election. A YouGov poll found that one in five voters intended to vote tactically at the 2024 General Election.

How tactical voting works

Under the first past the post system, votes for any candidate other than the winner do not contribute to the final result. This creates the phenomenon of so-called “wasted votes”. This can lead to outcomes where a more generally disliked candidate can win a seat despite a majority of the electorate having voted for other, similar candidates.

Consider a hypothetical constituency:

• Candidate A (right-of-centre): receives 40% of the vote.
• Candidate B (left-of-centre): receives 35% of the vote.
• Candidate C (left-of-centre): receives 25% of the vote.

In this scenario, Candidate A wins the seat, even though 60% of the electorate voted for a left-of-centre party. To prevent this, a voter whose first preference is Candidate C might pragmatically cast a tactical vote for Candidate B, as they are the left-of-centre candidate with the best chance of defeating Candidate A.

Supporters of electoral reform, including during the 2011 referendum on the alternative vote (AV), have argued that changing the voting system would reduce the need for tactical voting.

The rise of tactical voting guides

For tactical voting to work, voters need reliable information about the state of play in their specific constituency. During an election campaign, numerous websites emerge offering tactical voting recommendations based on polling data and analysis of previous results.

In 2019, several tactical voting sites appeared offering advice to prospective tactical voters. These included Best for Britain, the tactical.vote website, Turf out the Tories, Vote Smart, the Get Voting site, Remain United, and People’s Vote guide to tactical voting. Most of these organisations were Brexit-related and opposed to Britain’s withdrawal from the European Union. They attempted to solve the perceived problem of several Remain-supporting parties standing across the country.

Some of these groups, notably Best for Britain and its GetVoting.org campaign, returned to the tactical voting fray in the 2024 general election with an anti-Conservative message.

However, this advice can be problematic. Different campaign groups, often with similar aims, can use different methodologies and end up offering conflicting advice for the same constituency. For instance, in 2019, Remain United recommended voting Liberal Democrat in 50 seats; whereas Best for Britain, another organisation with the same objective, recommended 180 seats where supporters should vote for the Liberal Democrats.

​​A senior Labour party source told the Guardian that Best for Britain’s advice was “bogus”.

Why people may not vote tactically

Despite its effectiveness in 2024, tactical voting is not embraced by all voters. There are several reasons why many people choose to vote for their first-preference party, regardless of its chances of winning.

Many voters feel strongly that their vote should be a positive endorsement of the party and candidate they truly support, rather than a negative vote against someone they dislike.

Moreover, for many, voting is an expression of identity and long-standing loyalty to a political party. They cannot bring themselves to vote for a rival party, even one they dislike less than the main opponent.

Some voters may simply resent being told how to vote by tactical voting websites and campaign groups. They are often sceptical of the polling data and algorithms used, which have been unreliable in previous elections.

Tactical voting at the 2024 general election

The 2024 general election was shaped by highly sophisticated tactical voting across the country. After a long period of Conservative government, a widespread desire for change among voters created fertile ground for anti-Conservative tactical voting.

In many constituencies, this anti-Tory sentiment was strong enough to encourage voters to back whichever non-Conservative candidate was best placed to defeat the incumbent. This was particularly effective in so-called “blue wall” seats of conventionally Conservative, affluent commuter-belt constituencies in southern England.

The Liberal Democrats were a clear beneficiary of tactical voting, winning a record 72 seats. However, the party’s national vote share increased by only 0.6 points (11.6% to 12.2%) from 2019 to 2024.

Notably, the party made six gains in Surrey, five in Sussex, four in Oxfordshire and 11 in Devon and Somerset. Of those intending to vote for the Liberal Democrats, an estimated 35% cited tactical reasons – typically to oust an incumbent Tory.

In total, at least one in four voters planned to cast a tactical vote, according to research by the Electoral Reform Society (ERS).

Responding to the campaign, former Liberal Democrat leader Tim Farron said: “We believe the 2024 election, which saw a high level of tactical voting, demonstrates that the party is right to not pursue this strategy [of formal electoral pacts].”

The general election also saw a notable amount of informal cooperation between the parties. While there were no formal electoral pacts, anti-Tory opposition parties often focused their campaign resources away from seats where a different anti-government party was the clear challenger. In some cases, there were even reports of Labour party activists campaigning for the Liberal Democrats in places where the latter party was best-placed to win.

Tactical voting at 2019 general election

The 2019 United Kingdom general election was widely regarded as exceptional in modern British politics. The familiar left-right divide was disrupted by the politics of Brexit, which tested party loyalties and shaped voter behaviour.

The Conservative and Brexit parties supported Britain’s withdrawal from the EU, while Labour, the Liberal Democrats, the Scottish National Party (SNP) and the Greens were all critical of Brexit to some extent.

During the campaign, however, the Brexit Party, led by Nigel Farage, announced that it would not stand in constituencies which the Conservative Party won in 2017. This greatly reduced the amount of tactical voting necessary in the pro-Brexit camp. Farage had initially positioned the Brexit Party as a tactical voting tool for Brexit supporters, arguing that his party was mostly likely to win in historically Labour-voting areas.

Meanwhile, the aim of most tactical voting websites, which tended to be anti-Brexit, was to guide voter behaviour and prevent a Conservative majority.

In the end, the Conservatives under Boris Johnson won 365 seats with 43.6% of the vote. The Brexit Party, standing in only 275 constituencies, won no seats and just 2.0% of the vote. The more pro-Remain parties were much more evenly split. Jeremy Corbyn’s Labour Party won 202 seats and 32% of the vote. The Lib Dems, led by Jo Swinson, won only 11 seats and 11.6% of the vote.

Of course, Brexit was not the only issue shaping voter decisions. Tactical voting tends to rely on the salience (relative prominence) of a single issue or objective, and a common method/analysis. Other factors at play in the 2019 election included support for Johnson and opposition to Corbyn as Labour leader.

However, in its post-election analysis, the Best for Britain campaign claimed that some 800,000 people had voted tactically in line with their advice. The group said that Labour won six more seats as a result of their advice.

They pointed to the contest in Alyn and Deeside and the re-election of Mark Tami, the Labour incumbent. Tami was defending a majority of 5,235 in a constituency. Best for Britain reported that their website attracted 6,310 unique visitors from Alyn and Deeside, “including 910 on the last two days of campaigning.” The campaign group found that 23.9% of Lib Dem and Green voters cast their ballot tactically for Labour. Tami ultimately held the seat with a majority of 213 votes.

Electoral pacts and voter behaviour

Parties with similar political objectives will sometimes enter into formal electoral pacts. Under such arrangements, one party agrees not to stand in particular constituencies in order to maximise the chances of defeating a shared opponent. These pacts follow the same logic as tactical voting as an attempt to avoid vote “spoiling”.

However, formal pacts deliberately deprive voters of a choice to back an agreeable rival.

At the 2019 general election, the Greens, Plaid Cymru and the Liberal Democrats embraced a limited election pact, which saw the parties stand aside in dozens of constituencies to boost their partners’ chances. The deal covered 60 constituencies across England and Wales. Of the 60 constituencies, 10 had Green candidates only, including Brighton Pavilion, Bristol West, Bury St Edmunds, Cannock Chase, and Vale of Glamorgan.

This followed the Brecon and Radnorshire by-election in August 2019, which saw the Greens and Plaid Cymru stand aside in favour of the Liberal Democrats, with whom they shared an anti-Brexit stance. The Lib Dem candidate, Jane Dodds, narrowly defeated the Conservative candidate by 1,425 votes.

The Greens and Plaid Cymru achieved success with an electoral pact in 1992, which led to the election of a “hybrid” MP on a joint Plaid-Green platform in the constituency of Ceredigion and Pembroke North. In total, the joint campaign (operating as a result of the Llandysul Accord) stood in seven seats at the 1992 general election. Cynog Dafis, seen by some as the “UK’s first Green Party MP”, was elected as a result.

The Brexit Party’s decision to stand down in hundreds of constituencies at the 2019 general election could be understood in these terms.

Even in the absence of a formal pact, however, parties can deliver signals of implicit cooperation. Ahead of the 2021 Batley and Spen by-election. Ed Davey, leader of the Liberal Democrats, suggested that while his party would contest the seat, it would not commit the same level of resources as it had in the recent Chesham and Amersham by-election.

Davey said: “Liberal Democrat voters may well notice that this is a Labour-held seat with the Tories in a close second, and they’ll draw their own conclusions. But that shouldn’t be stitched up in a back room by party leaders.”

History of tactical voting and the 1997 election

Tactical voting is arguably at its most powerful when voters of various party affiliations coalesce around the shared objective of removing an incumbent. Historically, given the structure of the British party system, this dynamic has often operated to the detriment of Conservative incumbents.

In the years leading up to the 1997 general election, the Labour Party and the Liberal Democrats engaged in a notable degree of formal cooperation.

In March 1996, the Liberal Democrat and Labour parties began a series of talks on constitutional reform, led by Robin Cook (Labour) and Robert Maclennan (Lib Dems).

The group reported in March 1997. It agreed on proposals such as incorporation of the European Convention on Human Rights (ECHR) into UK law – which would bear fruit as the Human Rights Act 1998; freedom of information legislation – later the Freedom of Information Act 2000; and further constitutional reforms, including devolution, reform of the House of Lords, as well as a referendum on the voting reform for Westminster elections (to be agreed in a commission – later the ‘Jenkins commission’). Collectively, these proposals were referred to as the Cook/Maclennan agreement.

However, cross-party cooperation during the 1997 general election campaign was mostly tacit, despite private discussions over publishing a common programme. Lib Dem leader Paddy Ashdown is said to have drafted successive versions of a Lib-Lab ‘Partnership for Britain’s Future’. Opinion polling, however, suggested that the electoral risks of such explicit co-operation were too great.

The Mirror, the leading Labour-supporting tabloid, endorsed Liberal Democrat candidates in constituencies where Tony Blair’s party could not win. Labour consciously steered clear of Lib Dem target seats. And both parties withdrew their candidate in Tatton, clearing the way for BBC journalist Martin Bell’s successful campaign versus disgraced Conservative MP Neil Hamilton.

The extent of tactical voting, implicitly encouraged by the Liberal Democrat and Labour campaigns, was unprecedented at the 1997 election.

The Labour Party won 418 seats and a landslide majority of 179. The Liberal Democrats won 46 seats, improving their representation by a net 28. The Conservatives under John Major crashed to 165 seats – a net loss of 178.

Additional resources

• The British Election Study: https://britishelectionstudy.com/