Rightmove said prices were shooting up as a "supply/demand imbalance continues along with London's international allure".
"The average price tag on a newly-marketed property is £53,923 higher in September this year than last and if this trend were to continue it would hit £1 million in just over five years," said Miles Shipside, Rightmove director and housing market analyst.
"While we are not suggesting that this level of growth can or will be maintained, this extrapolation illustrates the desperate need for more building and more affordable housing in and around the capital," he added.
Across the country, prices were up 0.9% to £294,834 - a new national record.
The growth was driven by cheap borrowing but limited supply as some home-owners’ remained reluctant to move.
