Capital city dwelling values rose at a slower pace in April, lifting 0.3 per cent after a 2.3 per cent month on month rise in March, according to the RP Data-Rismark April home value index results.
The result also follows a 3.5 per cent increase over the first quarter of the year.
Home values fell most in Canberra, where they lost 1.1 per cent, and also shed 0.5 per cent in Melbourne.
The strongest rise in house prices was in Adelaide, with a 2.1 per cent lift.
Sydney prices rose 0.5 per cent in the month, while Perth gained 0.2 per cent, Hobart added 0.2 per cent and Darwin lifted 1.1 per cent.
RP Data head of research Tim Lawless said the reduction in the rate of capital gains would be a welcome relief for first home buyers.
“A lower rate of capital gains in Sydney and Melbourne, where dwelling values surged 22.5 per cent and 16.4 per cent respectively over the current growth cycle, may now signal that these markets are moving through their growth cycle peak," Mr Lawless said.
"However, we will need to see a few more months of data before we can establish whether a slowing trend is now evident in these cities.
"We have recently seen auction clearance rates move lower in both of these markets."
The survey found Sydney's median house price has surpassed $800,000 for the first time on record.
Over the three months to April, the median house price in Sydney was $802,000, which RP Data said likely reflected the increase in activity at the more expensive end of the city's housing market.
Sydney's median house price is 30 per cent higher than Melbourne's and 68 per cent higher in Brisbane's.