The rising risk of mortgage defaults across the country’s biggest housing markets is unlikely to trigger large-scale distressed sales as low unemployment, increasing demand for property and scarce supply will stabilise those same markets, a new PEXA report says.

The risks are increasing as owners in nearly half of all suburbs in NSW, or 181 postcodes, are likely to be at high risk of missing a mortgage payment by May – which the report by e-conveyancing platform PEXA said was the case for households paying up to 60 per cent of their income on mortgage payments.

This was a sharp increase from the three months ended December 2022, when only 118 postcodes were deemed at high mortgage risk.

In Victoria, owners in 74 postcodes – more than one in five suburbs – were at high risk of default, up from 44 in December and in Queensland, property owners across 19 postcodes were predicted to be at high mortgage risk, nearly double the December figure.

But even these scenarios – based on the assumption of a 0.5 of a percentage point increase in the benchmark lending rate by May – would not lead to widespread distress, PEXA head of research Mike Gill said.

‘‘I don’t think this will lead to massive fire sales because we’ve still got very low unemployment in Australia,’’ Mr Gill said.

‘‘For fire sales to occur, you have to see high unemployment where borrowers lose their jobs and they’re forced to make these selling decisions. We’re not seeing that.’’

Stresses on household budgets would hit owners differently, he said.

‘‘It’s more likely that this will be more nuanced, where some borrowers will really struggle to make their repayments and may be forced to sell.’’

AMP Capital chief economist Shane Oliver said there was still a risk that some home owners could be forced to sell as the full impact of the rate rises filtered through.

‘‘The full impact of the interest rate has yet to show up, as the economy slows, unemployment will rise, which could push some homeowners into distress,’’ he said.

Property owners in the more affluent postcodes are expected to face the highest mortgage risk, and PEXA predicts that these areas will account for 40 per cent of all high-risk postcodes across NSW and Victoria.

In Sydney, Northbridge (2063), Dural (2158) and Avalon Beach (2107) are the most at risk as the share of mortgage repayments is set to climb to 71.8 per cent, 71.4 per cent and 69.4 per cent of their family incomes, respectively.

The same trend is predicted across Melbourne, with Balwyn (3103), Balwyn North (3104) and Canterbury (3126) facing the biggest mortgage risk as the portion of repayments is predicted to rise to 74.2 per cent, 71.4 per cent and 70.2 per cent, respectively.