Sir Keir Starmer has led Labour to victory in the general election and is now prime minister after securing a majority in the House of Commons.
Speaking outside 10 Downing Street, he promised a government of service: "The work of change begins immediately."
Mr Starmer becomes only the fourth Labour leader to win a general election since World War Two.
After meeting the King at Buckingham Palace, he was greeted by flag waving supporters in Downing Street and clapped by civil servants as he entered Number 10.
While it was a brilliant night for Labour, the landslide victory fell just short of the 419 seats that Tony Blair won in 1997.
The race to be the UK's fastest election count was won by Houghton and Sunderland South in the North East, where Labour's Bridget Phillipson came out on top.
It was a terrible night for the Conservatives, who ended up with the lowest number of seats in the party’s history. Several senior figures, including Liz Truss and Jacob Rees-Mogg, lost their seats.
Rishi Sunak was re-elected in Richmond and Northallerton, but later said he would resign as Conservative Party leader.
Speaking outside Downing Street for the last time, he said: "I have heard your anger, disappointment and I take responsibility for this loss."
The Liberal Democrats benefitted from a collapse in Tory support and had a great night. Despite an action-packed campaign, Ed Davey still had enough energy to celebrate in central London in the early hours of Friday morning.
Nigel Farage, the leader of Reform UK, was another one to benefit from voters fleeing the Conservatives as he became an MP in Clacton at the eighth time of trying. The party won five seats in total.
It was also a successful night for the Green Party as they picked up four seats, including Brighton Pavilion where Siân Berry was elected to replace Caroline Lucas, the party's former leader.
Another veteran politican celebrating was former Labour leader Jeremy Corbyn, who was re-elected in Islington North as an independent candidate to loud cheers from supporters in the room.
In Scotland, Labour leader Anas Sarwar had a smile on his face after making big gains at the expense of the SNP and its leader John Swinney.
There were nearly 100 parties standing in constituencies across the UK in this election, including the Monster Raving Loony Party and Count Binface, a self-described "intergalactic space warrior".