City Hall said the initial target to start 8,000 homes by March 2030 had now been surpassed, with 8,283 starts as of the end of March 2025.
In May the mayor and the government announced a cut of more than 6,000 homes to the affordable homes programme, for 2021-2026, from the previous range of 23,900 to 27,100 starts.
The reduction – with a new target range of between 17,800 and 19,000 – represented a cut of 22%.
Lord Bailey, City Hall Conservatives’ housing spokesman, said: “Khan’s own government have set him the target of building 88,000 homes a year, in recognition of the acute housing crisis in London which is driving our rents and mortgages up.
“Today he’s proud to be announcing that he’s only met one eighth of that target.
“We want this government to succeed, for the sake of our city and our country – but Labour have clearly failed.”
Lord Bailey said “just 2.5% of his promised affordable homes” were completed despite receiving almost £9bn from the last government.
He added: “We need to move away from talking about ‘housing starts’ – you cannot live in a start, only a completion.”