Sydney and Canberra have dodged the trend of falling house prices across Australia's capital cities.

The RP Data-Rismark Hedonic Home Value Index for July show that capital cities on average have experienced a 2.9% year-on-year decline in value, falling 2.4% over the quarter. Falls were most evident in Brisbane (6.6%) and Perth (6.3%).

Sydney, meanwhile, saw marginal improvement of 0.5% year-on-year. Canberra experienced more robust growth at 1.9%.

Rismark economist Christopher Joye said Sydney's performance comes after more than a decade of growing below levels seen in other capitals such as Brisbane, Melbourne and Perth. While these markets are now experiencing declines, Joye said Sydney had proven "resilient".

"After years of being the perennial laggard, Sydney housing now looks to be a relatively resilient store of wealth," Joye said.