The 2015 United Kingdom general election was held on Thursday, 7 May 2015 to elect 650 members of Parliament (MPs) to the House of Commons. The Conservative Party, led by Prime Minister David Cameron, won an unexpected majority victory of ten seats; they had been leading a coalition government with the Liberal Democrats. It was the last general election to be held before the UK voted to leave the European Union (EU) in June 2016.
Opinion polls and political commentators had widely predicted that the election would result in a second consecutive hung parliament whose composition would be similar to the one elected at the previous general election in 2010. Potential coalitions and agreements between parties were intensively discussed; as a result, smaller parties received much more attention during the campaign than in previous UK elections. However, opinion polls underestimated the Conservatives, as they won 330 of the 650 seats and 36.9 per cent of the vote, giving them a small overall majority.
The opposition Labour Party, led by Ed Miliband, saw a small increase in its share of the vote to 30.4 per cent, but it won 26 fewer seats than in 2010, giving them 232 MPs. This was the fewest seats the party had won since the 1987 general election, when it had 229 MPs returned. Labour lost significant ground in Scotland to the Scottish National Party (SNP) who enjoyed a huge surge, winning 56 of the 59 Scottish seats, becoming the third-largest party in the House of Commons and the largest party in Scotland, knocking Labour from the status which it had held since 1964.
The Liberal Democrats, junior coalition partners led by Deputy Prime Minister Nick Clegg, suffered heavy losses, losing 49 of their 57 seats. Returning just eight MPs, it was their worst result since their formation in 1988. Cabinet ministers Vince Cable, Ed Davey, and Danny Alexander lost their seats, whilst Clegg only narrowly held his own seat. The UK Independence Party (UKIP) received 12.6 per cent of the vote, displacing the Liberal Democrats as the third-placed party in terms of popular vote, but won only one seat: Clacton, which they had gained at a by-election six months earlier. They failed to retain their other seat gained in a by-election, Rochester and Strood, and the party's leader, Nigel Farage, ran in South Thanet but narrowly fell short of winning the seat. The Green Party of England and Wales won its highest ever vote share of 3.8 per cent, and their only MP, Caroline Lucas, retained her seat, Brighton Pavilion. 
In Northern Ireland, the Democratic Unionist Party remained the largest party, the Ulster Unionist Party returned to the Commons with two seats after a five-year absence, and the Alliance Party lost its only seat of Belfast East, represented by Naomi Long for the party, despite an increase in their vote share. 
Following the election, Miliband and Clegg resigned their leaderships. Jeremy Corbyn succeeded Miliband as Leader of the Labour Party, while Tim Farron succeeded Clegg as Leader of the Liberal Democrats.
Despite speculation before the election that it would herald a new era of multi-party politics in the UK, it ended-up being the antithesis, marking a return to traditional two-party politics seen throughout the second half of the 20th century; Conservative–Labour domination would continue until the 2024 election. The SNP began a nine-year domination of Scottish Westminster seats. Charles Kennedy, who served as the leader of the Liberal Democrats from 1999 to 2006, made his last public appearance during the election campaign, in which he lost his seat; he died on 1 June 2015.
Notable MPs who retired at this election included former prime minister and Labour leader Gordon Brown, former Chancellor of the Exchequer Alistair Darling, former leader of the opposition and Conservative leader William Hague, and former leader of the Liberal Democrats Menzies Campbell. Notable newcomers to the House of Commons included future prime minister and Labour leader Keir Starmer; future prime minister, Conservative leader and Chancellor of the Exchequer Rishi Sunak, who also succeeded Hague as MP for Richmond (Yorks); future deputy prime minister and deputy Labour leader Angela Rayner and future SNP Commons leader Ian Blackford. Another future prime minister and Conservative leader, Boris Johnson, who had previously left Parliament in 2008 so he could serve as the mayor of London, returned to Parliament as MP for Uxbridge and South Ruislip.
It was the first of three general elections to be held under the rules of the Fixed-term Parliaments Act 2011. Local elections took place in most areas of England on the same day and is to date the most recent general election to coincide with local elections.
Election process.
The Fixed-term Parliaments Act 2011 led to the dissolution of the 55th Parliament on 30 March 2015 and the scheduling of the election on 7 May. There were local elections on the same day in all of England, with the exception of Greater London. No elections were scheduled to take place in Scotland, Wales, or Northern Ireland.
All British, Irish, and Commonwealth citizens over the age of 18 and residing in the UK who were not in prison or a mental hospital or a fugitive on the date of the election were permitted to vote. In British general elections, voting takes place in all constituencies in the United Kingdom to elect Members of Parliament to the House of Commons, the lower house of Parliament in the UK. Each constituency elects one MP using the first-past-the-post voting system. If one party obtains a majority (326) of the 650 seats, then that party is entitled to form the government. If no party has a majority, then there is what is known as a hung parliament. In this case, the options for forming the Government are either a minority government (where one party governs alone despite not having the majority of the seats) or a coalition government (where one party governs alongside party in order to get a majority of seats).
Although the Conservative Party planned for the number of constituencies to be reduced from 650 to 600, through the Sixth Periodic Review of Westminster constituencies under the Parliamentary Voting System and Constituencies Act 2011, the review of constituencies and reduction in seats was delayed by the Electoral Registration and Administration Act 2013. The next boundary review was set to take place in 2018, so the 2015 general election was contested using the same constituencies and boundaries as in 2010. Of the 650 constituencies, 533 were in England, 59 were in Scotland, 40 were in Wales and 18 were in Northern Ireland.
In addition, the 2011 Act mandated a referendum in 2011 on changing from the first-past-the-post voting system to an alternative vote system for general elections. The Conservative–Liberal Democrat coalition government agreed to holding a referendum. The referendum was held in May 2011 and resulted in the retention of the existing voting system. Before the previous general election the Liberal Democrats had pledged to change the voting system, and the Labour Party had pledged to hold a referendum on any such change. The Conservatives, however, promised to keep the first-past-the-post system, but to reduce the number of constituencies to 600. Liberal Democrats' plan was to reduce the number of MPs to 500, and for them to be elected using a proportional vote system.
The Government increased the amount of money that parties and candidates were allowed to spend on campaigning during the election by 23%, a move decided against the advice of the Electoral Commission. The election saw the first cap on spending by parties in individual constituencies during the 100 days before Parliament's dissolution on 30 March: £30,700, plus a per-voter allowance of 9p in county constituencies and 6p in borough seats. An additional voter allowance of more than £8,700 is available after the dissolution of Parliament. In total, parties spent £31.1m in the 2010 general election, of which the Conservative Party spent 53%, the Labour Party spent 25% and the Liberal Democrats 15%. This was also the first UK general election to use individual rather than household voter registration.
Date of the election.
An election is called following the dissolution of the Parliament of the United Kingdom. The 2015 general election was the first to be held under the provisions of the Fixed-term Parliaments Act 2011. Prior to this, the power to dissolve Parliament was a royal prerogative, exercised by the sovereign on the advice of the prime minister. Under the provisions of the Septennial Act 1715, as amended by the Parliament Act 1911, an election had to be announced on or before the fifth anniversary of the beginning of the previous parliament, barring exceptional circumstances. No sovereign had refused a request for dissolution since the beginning of the 20th century, and the practice had evolved that a prime minister would typically call a general election to be held at a tactically convenient time within the final two years of a Parliament's lifespan, to maximise the chance of an electoral victory for their party.
Prior to the 2010 general election, Labour and the Liberal Democrats pledged to introduce fixed-term elections. As part of the Conservative–Liberal Democrat coalition agreement, the Cameron ministry agreed to support legislation for fixed-term Parliaments, with the date of the next general election being 7 May 2015. This resulted in the Fixed-term Parliaments Act 2011, which removed the prime minister's power to advise the monarch to call an early election. The Act only permits an early dissolution if Parliament votes for one by a two-thirds supermajority, or if a majority of MPs pass a vote of no confidence and no new government is subsequently formed within 14 days. However, the prime minister had the power, by order made by Statutory Instrument under section 1(5) of the Fixed-term Parliaments Act 2011, to fix the polling day to be up to two months later than 7 May 2015. Such a Statutory Instrument must be approved by each House of Parliament. Under section 14 of the Electoral Registration and Administration Act 2013, the Fixed-term Parliaments Act 2011 was amended to extend the period between the dissolution of Parliament and the following general election polling day from 17 to 25 working days. This had the effect of moving forward the date of the dissolution of the Parliament to 30 March 2015.
Timetable.
The key dates were:
MPs not standing for re-election.
While at the previous election there had been a record 149 MPs not standing for re-election, the 2015 election saw 89 MPs standing down. Out of these MPs, 37 were Conservatives, 37 were Labour, 10 were Liberal Democrats, 3 were Independents, 1 was Sinn Féin and 1 was Plaid Cymru. The highest-profile members of parliament leaving were: Gordon Brown, the former Prime Minister, and William Hague, the former Leader of the Conservative Party and Leader of the Opposition. Alongside Brown and Hague, 17 former cabinet ministers stood down at the election, including Stephen Dorrell, Jack Straw, Alistair Darling, David Blunkett, Sir Malcolm Rifkind and Dame Tessa Jowell. The highest-profile Liberal Democrat to stand down was their former leader Sir Menzies Campbell, while the longest-serving MP, Sir Peter Tapsell, also retired, having served as an MP continuously since 1966, or for 49 years.
Contesting political parties and candidates.
Overview.
On 9 April 2015, the deadline for standing for the general election, there were 464 political parties registered with the Electoral Commission. Candidates who did not belong to a party were either labelled as an Independent or not labelled at all.
The Conservative Party and the Labour Party had been the two biggest parties since 1922. Every prime minister to serve since 1935 had been the leader of the Conservatives or Labour. Opinion polls had predicted that the two parties would receive a combined total of anywhere between 65% and 75% of votes, and would receive anywhere between 80% and 85% of the seats; and that, as such, the leader of one of the two parties would become the Prime Minister (David Cameron of the Conservatives or Ed Miliband of Labour) after the election. The Liberal Democrats had been the third largest party in the UK for many years; but as described by various political commentators, other parties had risen relative to the Liberal Democrats since the 2010 election. In order to emphasise this, "The Economist" stated that "the familiar three-party system of the Tories, Labour, and the Lib Dems appears to be breaking