The average price of a newly listed home in Britain fell in June — an unusual turn for a month that normally brings modest gains — in the latest sign that the country's housing market has slowed and the advantage has shifted from sellers to buyers.

A rare June fall

The asking price of newly marketed homes dropped 0.6% to £376,191, according to Rightmove's House Price Index, the steepest June decline the property portal has recorded in about 14 years. Prices are now around 0.5% lower than a year ago. "It's unusual to see a price fall of this size in June," said Colleen Babcock, a property expert at Rightmove, noting that the month has typically delivered a small rise over the past decade.

Too many homes, too few buyers

Behind the dip is a simple imbalance: there are a lot of homes for sale and fewer eager buyers. The number of properties on the market is among the highest for this time of year in a decade, while new buyer demand has fallen sharply and agreed sales have slipped from a year earlier, Rightmove said. More than a third of newly listed homes are failing to find a buyer — a reminder of the cost of overpricing in a market where purchasers can afford to be choosy.

Buyers in the driving seat

The cause is no mystery. Mortgage rates, though they have edged down slightly — the typical two-year fixed rate has eased to around 5.07% — remain high by the standards of the past decade, squeezing what buyers can afford and making them slower and more selective. That has handed leverage to purchasers, who are negotiating harder and walking away from homes that do not stand out on price. Sellers, the estate agent Jeremy Leaf said, have been "obliged to accept a larger dose of realism" on their asking prices.

A reset, not a slump

Industry figures were careful not to read the numbers as a collapse. Nathan Emerson, chief executive of the agents' body Propertymark, suggested the market was "continuing to find a more sustainable balance, rather than experiencing a loss of confidence." For sellers, the message is to price keenly from the start; for buyers, the summer brings more choice and more room to bargain than they have had in some time — a shift in fortunes that, for now, defines Britain's housing market.