House prices fell by 0.4% in August, compared with July's figures, taking the average value of a home to £160,256.
Prices in the three months to August were 0.3% lower than the previous quarter, and 0.9% below the figures for the same period last year, according to the Halifax house price index.
"Overall, there has been little change in house prices so far this year with the UK average price in August at a very similar level to the end of 2011," says Martin Ellis, Halifax's chief housing economist.
Prices have been drifting slowly downwards since the start of the year, with the average price of a property in August falling by £669 from £160,925 in January 2012.
Martin Ellis says prices are likely to remain flat for the rest of the year at least.