Transactions are now down by up to a third across all UK regions, Land Registry data shows.
The latest Land Registry House Price Index reveals residential sales figures for June, showing the number of transactions was down 21.5% annually, while regions such as the east of England and London have seen 28.6% and 31.3% declines respectively.
The south west and south east of England have also each seen sales volumes decline by 25% annually.
Sales on a monthly basis have fared better, up 5.1% across the UK between May and June, the Land Registry said, which is also the second consecutive month of increases.
Annual price growth also slowed in the year to August, from 3.4% in July to 3.2%, putting average UK prices at £232,797.
This is up just 0.2% on a monthly basis.
House prices grew fastest in the east Midlands, increasing by 6.5% in the year to August 2018, while London saw values decline by 0.2%.
Commenting on the figures, Andy Sommerville, director at conveyancing software provider Search Acumen, said London was taking the brunt of the lull in the market, with sales in the first half of 2018 down by almost a quarter compared with the same period last year.
Search Acumen research found there were 26,995 properties sold in London in the first half of 2017, compared with 20,831 in 2018.
Sommerville said: “As another month passes, house price growth continues to lose steam across the country.
“The end to the seller’s market appears to be looming and property investors will be taking stock of their portfolios and assessing where might be most impacted by a lull in valuations.
“We turn towards the Chancellor’s Budget for continued support for UK housing in order to ensure the market works for both buyers and sellers alike.”