It found that the average asking price for homes in England and Wales dropped by 0.4 per cent or £1,172 in June, the first time it has fallen in this month since 2009.
This means the annual rate of growth slowed to 1.8 per cent – the smallest since April 2013.
Prices in most UK regions rose, but a 2.4 per cent drop in London together with smaller declines in southeastern England and the West Midlands dragged down the overall average.
“The price of property coming to the market had increased in June in every year since 2009, so buyers’ confidence has clearly been affected by inflation outstripping their pay packets and current political events,” Rightmove director Miles Shipside said.
But Shipside insisted that demand was still strong, especially among first-time buyers “aided by the cheap cost of borrowing”.