- Watch the quickest results and unrivalled expert analysis through the night on Election 2019 Live: The Results
The Conservatives have secured a parliamentary majority and are heading for a landslide victory in the 2019 General Election as traditional Labour seats held by the party for a generation have turned blue.
Jeremy Corbyn has confirmed he won't contest another election as Labour leader on a night of shocks, which included a narrow defeat for Lib Dem leader Jo Swinson.
Ms Swinson announced her resignation as Liberal Democrat leader after she lost her East Dunbartonshire by less than 150 votes to the SNP, with Sir Ed Davey and Baroness Sal Brinton filling the void until a leadership election is held in the new year.
Boris Johnson thanked British voters for delivering the Conservatives a "powerful, new mandate to get Brexit done" at his constituency count in Uxbridge.
US president Donald Trump congratulated Mr Johnson on his electoral success and tweeted it will pave the way for a "bigger" and "more lucrative" trade deal between the UK and US.
The Conservatives were tipped for their biggest majority since Margaret Thatcher with a majority of around 80, with Labour expected to scrape above 200 seats.
The joint BBC/ITV News/Sky Exit Poll had predicted the Tories gaining 368 seats - a majority of 86 - with Labour tumbling to 191 seats, their worst result since 1935.
In what was a bellwether for results throughout the night, Blyth Valley, which has never had a Conservative MP, became the first red seat to turn blue.
Workington - a key Leave-voting constituency targeted by the Tories - also saw a huge swing from Labour to the Conservatives, with Darlington also following suit.
Wrexham, which has been a Labour stronghold since 1935, fell to the Conservatives. Labour's share of the vote collapsed by 9.9 per cent from 2017, allowing the Tories to take control.
Even Redcar, 135th on the list of target seats for the Conservatives, fell out of Labour's control before Tony Blair's former Sedgefield constituency went blue.
Bolsover, which had been represented by veteran Labour MP Dennis Skinner for 49 years, also fell to the Tories.
Boris Johnson thanks the nation for backing the Conservatives
The prime minister arrived at his Uxbridge constituency count with his girlfriend Carrie Symonds and their dog Dilyn.
The Conservative leader was reluctant to boast about his electoral success, pointing out there was still a long way to get before his party had officially secured a majority.
Mr Johnson said: "Clearly lots of results are still coming in and we're still mainly dealing with projections but at this stage it does look as though this One Nation Conservative government has been given a powerful new mandate to get Brexit done."
He added: "Above all, I want to thank the people of this country for turning out to vote in a December election that we didn't want to call.
"But I think has turned out to be a historic election which gives us now, in this government, the chance to respect the democratic will of the British people, to change this country for the better and to unleash the potential of the entire people of this country.
"And that is what we will now do, and if we are lucky enough to be returned, as the exit polls seem to suggest, then that work will begin tomorrow... or as I should say, not tomorrow, today!"
Mr Johnson later told jubilant aides in Conservative HQ: "We must understand now what an earthquake we have created.
"The way in which we have changed the political map of this country.
"We have to grapple with the consequences of that, we have to change our own party, we have to rise to the level of events, we must, we just answer the challenge that the British people have given us."
What was Corbyn's reaction to Labour's disappointing night?
In a speech at his Islington North constituency, Mr Corbyn confirmed he would not stand as party leader for another general election, but refused to say whether he would stand down.
He said: "I want to make it clear that I will not lead the party in any future general election campaign.
"I will discuss with our party to ensure there is a process of reflection on this result and on the policies that the party will take going forward."
He added: "I will lead the party during that period to ensure that discussion takes place as we move on into the future."
Mr Corbyn blamed Brexit for "polarising" political debate in Britain and for Labour's poor showing at the election but said his policies remained popular with the public.
He said: "This is obviously a very disappointing night for the Labour Party with the result that we've got.
"All of those policies were extremely popular and remain policies that have huge popular support across this country.
"However, Brexit has so polarised and divided debate in this country, it has overridden so much of the normal political debate and contributed to the result for the Labour Party across the country."
While Labour managed to hold onto Newcastle Central and Sunderland South, both traditionally safe Labour seats in the North East, its vote share was down around 3,000 and 9,000 votes respectively.
Meanwhile Putney, an affluent Remain-voting constituency on the outskirts of London, bucked the trend with Labour taking control from the Tories.
Labour also held onto the Remain-backing Canterbury and Battersea seats as it began to shed its typically working-class strongholds in the North East and the Midlands to the Conservatives.
The DUP's deputy leader Nigel Dodds lost his seat in what proved to be a disastrous election for his party.
The DUP, whose 10 MPs were crucial power-brokers in the last hung parliament, lost two of their 10 MPs.
The 2019 election also saw more nationalist and republican MPs elected more than unionists in Northern Ireland.
And following Jo Swinson's resignation as Lib Dem leader, Sir Ed Davey and Baroness Sal Brinton were announced as acting leaders until a leadership campaign is to be held in the new year.
In a statement, Swinson said: "Tonight's result is obviously hugely disappointing, in East Dunbartonshire, and across the whole country with Boris Johnson winning a majority.
She added: "This is clearly a setback for liberal values. But there are millions of people across the country who believe in them. By coming together to fight for them, we can create a positive future."
The SNP are forecast to be the third biggest party in parliament with 48 of the 59 seats in Scotland, while the Lib Dems are forecast to gain 13 seats in total.
The Brexit Party has failed to win a seat while other parties total 23 seats.
The Exit Poll, conducted by Ispos Mori for the joint election broadcasters, is on the basis of 22,790 interviews in 144 polling stations across Great Britain.
What has the Conservative reaction been?
Boris Johnson tweeted shortly after the exit poll was announced to thank volunteers for supporting his campaign.
The prime minister, who is watching the results in Number 10, said: "Thank you to everyone across our great country who voted, who volunteered, who stood as candidates. We live in the greatest democracy in the world."
Cabinet minister Michael Gove told Tom Bradby the exit poll has proven that voters want the EU referendum result honoured.
He said: "If this result is right, it seems to me to reinforce one particular point, and that's Jeremy Corbyn's leadership of the Labour has proved to be an impediment to moving this country forward and allowing the Labour Party to heal and rebuild."
He added: "If its anything like the opinion poll you've shown, it's that people want to make sure that the Brexit vote was honoured and that Jeremy Corbyn's uncertainty on that has clearly hurt the Labour Party, if this exit poll is correct."
Fiona Hill, Theresa May's former chief of staff, admitted the result from this election was "exactly" the sort of performance the Conservatives wanted in 2017.
She said the "template" of winning over Labour leave seats was set in 2017, but unlike Mr Johnson, they were unable to win over those voters.
Ms Hill said: "A lot has happened in two years, we've had a lot of different votes in parliament that were blocked so I think the context is slightly different this year.
"And I think that Boris ran a fairly somber but steady campaign. There weren't too many surprises, give or take... all in all, he's got what he wanted because he's worked hard, kept his head down, and worked out finesse lines like 'get Brexit done'."
What's the reaction to the Exit Poll?
Former Chancellor George Osborne said: "We are entering the Boris Johnson era of British politics.
"It's been very much his election and this gamble that he's taken would have paid off."
Mr Osborne added: "He's won by uniting the Remain vote and splintering the leave vote."
Former shadow chancellor Ed Balls said: "There will be Labour candidates and activists all across the UK with that deep, sickening feeling. This is a catastrophe and a battering for the Labour Party."
Shadow equalities minister Dawn Butler admitted Labour's bad performance at the polls was down to Brexit.
She said: "It seems like it will be an extremely disappointing result."
She added: "But ultimately this defeat will be down to one thing, and that'll be Brexit and the divisions across the country in regards to Brexit."
Former Labour Home Secretary Michael Johnson said the exit poll was "terrible" for his old party.
He said: "I never dreamt for a moment that we would go below 200 seats, that is terrible. If you look at the Labour party in opposition... you always saw in successive elections that vote building.
"This is the fourth election in and we've gone backwards."
Meanwhile in Scotland, the SNP is on course for a landslide win north of the border, with exit polls suggesting she could sweep up 55 of the 59 seats up for grabs.
Nicola Sturgeon said while it was a "good night" for her party, the overall result for the rest of the country was "grim".
A successful night for Ms Sturgeon's party could also increase pressure on Westminster to hold another Scottish independence referendum, with a divide between Remain-voting Scotland and the rest of the country increasing.
George Osborne said while the SNP looked to have performed well at this election, he did not think it would lead to another independence vote for Scotland.
Mr Osborne, who was part of the Conservative government who campaigned at the 2014 referendum for Scotland to remain part of the UK, said: "I don't think he will ever concede another referendum on independence.
"I don't think any Conservative leader who went through the experience of 2014 referendum on Scottish independence wants to repeat that sense of putting the union up for grabs."
Allegra Stratton disagreed with the Evening Standard editor. She said: "When I was in Scotland, it wasn't really about Brexit, it was about, for many people, fear of the break-up of the UK."
"It may be that pro-union sympathy was split between various party and so, on the surface, she's had a great night... but actually when you drill down, it was that those pro-union voices were split.
ITV News Election Expert Professor Colin Rallings said: "This turned out to be the Brexit election.
"It's quite clear that the Conservatives have done best in the areas which voted most heavily to leave three years ago. Labour has been struggling to hang on."
He added: "Labour are looking to fall below 200 seats, which is a terrible result for them. It would be their lowest number of seats since 1935."
ITV News National Editor Allegra Stratton said: "People were saying we want to get Brexit done, even if it was the wrong colour.
"There were prepared to vote for somebody who they hadn't voted for before, and there were other people who were saying we will lend the Conservatives our vote, so there's a range of people why Labour people voted Conservative."
Who could be the next Labour leader?
Labour's poor performance at this election will focus attention as to who could take over from Mr Corbyn as party leader.
William Kedjanyi, Star Sports political analyst, said Sir Keir Starmer was the favourite to take over at 3/1, but that people within the party wanted a woman to take over.
One of the frontrunners to be next Labour leader was Laura Pidcock, but she lost her North Durham seat to the Conservatives.
Mr Kedjanyi said: "The general thinking from people that I talk to in Labour is that they want a woman in charge. Rebecca Long-Bailey was high on that list but again, the exit poll puts her in trouble.
"It's a really fluid market but there's a lot of opportunities because many of these names might not be in the parliamentary Labour Party in the morning."
Jon Lansman, founder of the Corbyn-supporting Momentum group, blamed the defeat on Brexit and said the Labour Party's policies resonated with voters across the country.
Mr Lansman said: "On austerity, he has completely changed the narrative.
He added: "Jeremy Corbyn, even before he became leader, destroyed the universal assumption that there was no choice but to deliver austerity, such that the Tories are no longer pursuing that narrative."
Former shadow home secretary Ed Balls disagreed, claiming that Labour's performances under Mr Corbyn at the past two elections highlighted a weakness in the party.
Mr Balls said: "We've just seen the lowest number of Labour MPs in our history, the biggest fall in our voting share in our history.
"Jeremy Corbyn has now lost two elections... so don't we just have to reach a conclusion from that?"
Former Labour cabinet minister Alan Johnson was scathing in his criticism of Mr Corbyn and Momentum.
He claimed their "far-left" politics had made the party virtually undetectable.
Mr Johnson said: "The working classes have also been a disaster for Jon and his kind. Corbyn has been a disaster on the doorstep. Everyone knew that he couldn't lead the working class out of a paper bag.
"Now Jon's developed this Momentum group, this party within the party aiming to keep the purity. The culture of betrayal goes on.
"You'll hear it now more and more over the next coming days as this little cult get their act together.
"I want them out of the party. I want Momentum gone. Go back to your student politics."