London has 585 one bed flats on the market at £1m or more according to research by online agency HouseSimple.
HouseSimple says some are extraordinarily small, despite the seven-figure price tag.
It claims that the smallest is in Westminster and is on sale through CBRE for £1.04m and measures just 416 square feet; “that’s a fifth of the size of a singles tennis court” says the online firm.
The most expensive one-bed flat is in Knightsbridge, and is currently on the market through Croft International with a guide price of £4.95m.
HouseSimple, which has used Zoopla property listings as the basis for its research, says 27 per cent of these £1m plus flats are in the borough of Lambeth, while another 23 per cent are located in the City of Westminster, and 22 per cent in the Royal borough of Kensington and Chelsea.
Sam Mitchell, HouseSimple chief executive says: “Affordability has been a major issue for the average buyer, but we have also seen the top end of the market struggle with fewer overseas investors looking at the capital as a safe haven for their money. We could well see a further correction over the coming months, particularly if Brexit negotiations don’t make sufficient progress.”