A record 314,000 redundancies were recorded in the three months to September as the coronavirus took a further toll on jobs.
Figures from the Office for National Statistics (ONS) also showed the unemployment rate rose to 4.8%, its highest level since November 2016 and up from 4.5% the month before.
ONS data for October also suggested that the number of employees on UK payrolls has fallen by 782,000 since March.
The jobs crisis is expected to worsen over coming months.
Last week the Bank of England said it expects unemployment to reach 7.75% by the second quarter of 2021.
The UK economy was plunged into the steepest recession on record earlier this year.
Figures later this week are expected to show a partial recovery in the third quarter.
But the pick-up in activity was not enough to spare hundreds of thousands of workers from being axed, with the ONS pointing to strong growth in redundancies in the first two weeks of September.
That took its heaviest toll on those aged 16-24 – with the group seeing redundancy rates more than double compared to the same period a year ago.
New lockdown measures across England look set to throw the UK back into a renewed contraction as 2020 draws to an end.
Chancellor Rishi Sunak has extended the furlough scheme subsidising wages for temporarily laid-off workers until the end of March.
Responding to the latest jobless numbers, Mr Sunak said: “Today’s figures underline the scale of the challenge we’re facing.
“I know that this is a tough time for those who have sadly already lost their jobs, and I want to reassure anyone that is worried about the coming winter months that we will continue to support those affected and protect the lives and livelihoods of people across this country.”