Property prices in Chelsea have hit £11,321 per square metre - five times the national average, and ten times as much as the UK's cheapest areas.
According to new research from Halifax, prices per square metre in London have been rising nearly twice as fast as those in the rest of the country since 2011.
There are now 17 areas in Greater London with an average price of more than £5,000 per square metre. Kensington and Chelsea is still Britain's most expensive neighbourhood, followed by Westminster at £10,552 and Camden at £9,012 per square metre.
"There has been a marked widening in the north-south property divide over the past two decades as prices per square metre have risen by 432% over this period in Greater London – more than twice the increase in areas outside of southern England," says Chris Gowland, mortgages director at Halifax.
"The consistent gap between southern England – led by London – and the rest of the country over the past two decades – is a trend that has embedded itself throughout the last five years."
Only five areas outside southern England fetch a higher property price per square metre than the national average of £2,216 – Solihull and Leamington Spa in the West Midlands, Altrincham in the North West, Scotland's capital Edinburgh and Harrogate in Yorkshire.
With an average price of £1,019 per square metre, that's less than a tenth of the average price per square metre in Kensington and Chelsea.
Of the 10 towns with the lowest prices per square metre, four are in Scotland and two in Wales. The four English towns with the lowest house prices on a per square metre basis are all in northern England – Scunthorpe, Accrington, Hartlepool and Wallasey.
In Hartlepool, for example, £11,321 won't just buy you one square metre - it'll get you a whole two-bedroom house. There's a two-bed terrace currently up for sale with a guide price of £10,000, for example, that boasts double glazing, gas central heating and a new kitchen. It also has the great advantage of being big enough to allow the owner to lie down.
The 10 most expensive areas per square metre
Kensington and Chelsea, Greater London: £11,321
Westminster, Greater London: £10,552
Camden, Greater London: £9,012
Hammersmith and Fulham, Greater London: £8,635
Islington, Greater London: £7,964
Wandsworth, Greater London: £6,959
Hackney, Greater London: £6,860
Southwark, Greater London: £6,484
Richmond upon Thames, Greater London: £6,446
Tower Hamlets, Greater London: £ 6,432
The 10 most expensive towns per square metre outside London
Solihull, West Midlands: £2,661
Leamington Spa, West Midlands: £2,645
Altrincham, North West: £2,634
Edinburgh, Scotland: £2,355
Harrogate, Yorkshire and Humberside: £2,342
Aberdeen, Scotland: £2,191
Sutton Coldfield, West Midlands: £2,113
Chester, North West: £1,973
Bromsgrove, West Midlands: £1,970
Stourbridge, West Midlands: £1,943
The 10 least expensive towns per square metre
Airdrie, Scotland: £1,019
Llanelli, Wales: £1,028
Scunthorpe, Yorkshire and Humberside: £1,036
Lanark, Scotland: £1,040
Accrington, North West: £1,055
Hartlepool, North: £1,062
Neath, Wales: £1,065
Wallasey, North West: £1,067
Coatbridge, Scotland: £1,071
Kilmarnock, Scotland: £1,120