The number of house sales fell by 16% in August compared with the same month a year earlier, according to provisional figures from HM Revenue & Customs (HMRC).
An estimated 87,010 home sales took place across the UK last month, which was 16% lower than in August 2022 but 1% higher than July 2023.
It was the weakest August for house sales since 2020, when the market was dealing with the impacts of the coronavirus pandemic.
Mortgage rates have jumped as the Bank of England (BoE) base rate has increased, although there have been recent signs of fixed mortgage rates easing back amid expectations over inflation.
The BoE uses base rate increases to curb inflation, but last week it left the rate unchanged.
Figures from financial information website Moneyfacts show the average five-year fixed-rate mortgage on the market dipped below 6% for the first time since July.
On Friday, the average was 5.98%, down from 5.99% on Thursday, according to Moneyfacts.
Alex Lyle, director of London-based estate agency Antony Roberts, said:
"The hold in base rate may give hope that there's longer-term stability on the way with regards to mortgage pricing, which in turn should improve the confidence of those anxious about committing to a purchase."
Nicky Stevenson, managing director at estate agent group Fine & Country, said:
"Affordability pressures means sales are understandably lower than last year, though last week's base rate freeze has injected another dose of confidence in the property market.
"The suggestion that we may have nearly reached the peak in interest rates is encouraging more people to begin or resume their house search.
"This, combined with the traditional seasonal spike in demand, is helping to drive increased activity this autumn."
By Vicky Shaw, PA Personal Finance Correspondent