Turnout: 68.80%
About this election
The general election of 8 June 2017 was a snap contest called by Conservative prime minister Theresa May, three years early, in the expectation of a crushing majority to strengthen her hand in the Brexit negotiations. Instead it produced a hung parliament. The Conservatives won the most seats — 317 on 42.34% of the vote — but lost their majority, while Jeremy Corbyn's Labour Party surged to 262 seats and 39.99%, the party's biggest vote-share increase since 1945. May was forced to govern with the support of Northern Ireland's Democratic Unionist Party. Turnout rose to 68.8%.
As in every Westminster election, the 650 MPs were chosen by first-past-the-post in single-member constituencies, with the party able to command a Commons majority forming the government. A working majority requires 326 seats (or slightly fewer in practice, because Sinn Féin's MPs do not take their seats and the Speaker does not vote).
Having become prime minister without a general election when Cameron resigned after the Brexit referendum, May enjoyed poll leads of around 20 points in early 2017. She argued that a personal mandate and a larger majority were needed to deliver Brexit and resist obstruction in parliament, and reversed her earlier insistence that there would be no early election.
The campaign went badly for the Conservatives. Their manifesto included a social-care funding plan — quickly dubbed the "dementia tax" — that proved deeply unpopular and was hastily revised, undermining May's "strong and stable" message. Corbyn, written off by many commentators, ran an energetic, retail-politics campaign promising to abolish tuition fees and end austerity, and drew large crowds. The campaign was also overshadowed by two terrorist attacks, the Manchester Arena bombing and the London Bridge attack, which briefly suspended national campaigning.
The Conservatives gained vote share but lost seats on a swing to Labour, ending up 8 short of a majority. Labour's recovery — up 32 seats — confounded expectations and strengthened Corbyn's position within his party despite finishing second. The two main parties together took over 82% of the vote, the highest combined share since 1970, as the UKIP vote collapsed and largely returned to the Conservatives and Labour.
UKIP, having achieved its goal of a Brexit referendum, fell from 12.6% to 1.84% and lost its only seat. The Liberal Democrats edged up to 12 seats despite a lower vote share, and in Scotland the SNP, while remaining dominant with 35 seats, lost 21 to a Conservative and Labour revival, as the Scottish Conservatives under Ruth Davidson enjoyed their best result in a generation.
Without a majority, May negotiated a confidence-and-supply agreement with the DUP's 10 MPs, who agreed to support the government on key votes in return for additional funding for Northern Ireland. The arrangement kept the Conservatives in office but left May dependent on a small party and on her own restive backbenchers, a weakness that would dog the Brexit process.
The seat map looked broadly similar to 2015 — Conservative strength across southern and Midlands England, Labour ahead in the North, London and Wales, the SNP first in Scotland and the DUP in Northern Ireland — but the margins narrowed almost everywhere, with Labour gaining ground in cities, university towns and parts of the South. Click a region for its full breakdown.
Policy played an unusually large part in the campaign's turn. Labour's manifesto, "For the Many, Not the Few", promised to renationalise the railways, water, mail and energy, abolish university tuition fees and raise taxes on the highest earners and large companies; leaked early, it proved popular and gave Corbyn's campaign momentum. The Conservative manifesto, by contrast, offered few giveaways and contained the ill-fated social-care plan, alongside proposals to means-test winter fuel payments and weaken the pensions "triple lock" — retreats that alarmed the older voters who form the core of the Conservative vote and forced an embarrassing mid-campaign reversal.
Labour's recovery was widely attributed to a surge of support and turnout among younger and university-educated voters, drawn by the pledge to scrap tuition fees and by Corbyn's anti-austerity message — a phenomenon quickly dubbed the "youthquake", even if pollsters later disputed its precise scale. Labour also won back many Remain-leaning voters who had drifted to the Greens and Liberal Democrats, while the disintegration of the UKIP vote split between the two main parties rather than flowing wholesale to the Conservatives as May had assumed.
The result fatally weakened May's authority. Unable to pass her Brexit withdrawal agreement through a divided Commons over the following two years, she resigned in 2019 and was succeeded by Boris Johnson, who would seek a fresh mandate of his own at the end of that year.
Constituency results compiled by the House of Commons Library — commonslibrary.parliament.uk.
Compiled and reviewed by Bartłomiej Paruzel, Election Data Analyst, from official results. See our data methodology.