The total spent this year smashed the previous record of £36.6b in 2007 and was up almost 60 per cent on 2020 partly because of the rapid house price inflation over the past 12 months.
While the high number of transactions has been a nationwide phenomenon this year, the increase in Londoners buying outside the capital has been particularly pronounced, according to the study.
By forcing offices to close or reduce capacity, Covid-19 has triggered a spike in homeworking, which looks set to be sustained at least into the first quarter of 2022 because of the rapid spread of the Omicron coronavirus variant.
That is one reason why movers are contemplating properties further afield than they might have done previously, said Neal Hudson, director of housing market research company Residential Analysts.
"There's been a general reassessment of housing, with people no longer needing to commute as they used to. That is particularly true in London," he said.
The prospect of spending more time working at home has prompted what estate agents describe as a "race for space", with buyers looking for larger homes with gardens over city centre flats.
Flats have also lost some of their shine as a result of the cladding safety scandal in the aftermath of the Grenfell tower fire in 2017, which has overwhelmingly affected apartment blocks built over the past 20 years.
The pandemic was largely responsible for the exceptionally high number of people leaving the UK capital city this year, said Aneisha Beveridge, head of research at Hamptons, adding that "2021 is likely to mark the largest out migration from London for at least a generation".
She added: "After this year's frenzy, we expect the numbers to fall back a little, particularly as house prices outside the capital are set to continue outperforming London over the next few years."
But the majority buying outside Greater London had remained within the capital's orbit, the study found. Almost half bought in the south-east and a quarter in the east of England. The commuter towns of Dartford, St Albans and Elmbridge were particular hotspots, according to Hamptons.
Over the last three decades, residents have tended to leave London from their mid-30s, as they start families and look for larger, more affordable properties. The population of the city kept growing during that time because of immigration from the EU and a higher level of births than deaths.
But Hudson and Beveridge suggested that, if sustained, the higher outflows coupled with slower inward migration post-Brexit could slow the growth of the capital's population.
"If there is downward pressure on the size of London's population, that could put some downward pressure on house prices and rents," said Hudson.
Written by: George Hammond
© Financial Times