- He won nine of the 14 constituencies including two gains from the Tories.
- More than 2.4m votes were cast reflecting a turnout of 42.8% - ever so slightly down compared to the 2021 mayoral election.
Labour's Sadiq Khan has won a landmark third successive term as mayor of London.
Mr Khan, who was first elected in May 2016, beat his Conservative rival Susan Hall by more than 276,000 votes - representing a swing of 3.2% to Labour.
He won nine of the 14 constituencies including two gains from the Tories.
More than 2.4m votes were cast reflecting a turnout of 42.8% - ever so slightly down compared to the 2021 mayoral election.
Speaking after his victory was declared at City Hall in east London, Mr Khan said: "It is the honour of my life to serve the city that I love."
"I am beyond humbled right now," he added. "It has been a difficult few months.
"We faced a campaign of non-stop negativity. I am proud we answered fearmongering with facts.
"It is truly an honour to be re-elected for a third term and an increased margin of victory. Today is not about making history it is about shaping our future."
Mr Khan also used his victory speech to urge Prime Minister Rishi Sunak to call a general election.
His main rival Ms Hall then congratulated Mr Khan on his victory as she said campaigning to be mayor had been an "honour and privilege".
"I will continue to hold Sadiq to account, for hard-working families, motorists and women," she said. "I urge Sadiq to make London better for all our sakes."
Counting started at 09:00 BST on Saturday and all candidates are expected to appear at City Hall later for an official announcement.
Mr Khan won constituencies including Lambeth & Southwark, Barnet & Camden, City of London & East, Merton & Wandsworth, Greenwich & Lewisham, Enfield & Haringey and North East - all of which he won at the last contest in 2021.
He gained West Central from the Conservatives, with a 5.2% swing to Labour from the Tories, and South West from the Tories with a 2.7% swing.
Ms Hall held outer London boroughs of Havering & Redbridge, Croydon & Sutton, Bexley & Bromley, Ealing & Hillingdon and Brent & Harrow.
Overall Mr Khan won just under 1,088,225 votes comfortably beating Ms Hall who secured 811,518 votes.
The Liberal Democrats edged the Green Party to third place, while Reform UK's candidate Howard Cox finished fifth with 3.2% of the overall vote.
Speaking at City Hall ahead of the official results, London Assembly's Labour group leader Len Duvall effectively called the election result for Mr Khan.
Mr Duvall told the Local Democracy Reporting Service: "I think the trends are there. I think this looks like Sadiq has crossed the line and has got a third term."
He believes Liberal Democrat and Green voters appear to have "lent" their support on the mayoral ballot to Mr Khan, while Reform UK took votes from the Conservatives.
The former Conservative Minister for London was critical of Ms Hall and said the Tories ran an "incredibly underwhelming campaign".
Paul Scully, who stood unsuccessfully in the Conservative's selection process to be its mayoral candidate, told the BBC the Tories had "gifted" Mr Khan a third term.
Counting continues for London Assembly constituency members and a London Assembly London-wide members.
Those results are expected later on Saturday.