A property analyst is predicting up to a quarter of residential property listings will sell at a loss if mortgage rates continue their upward trajectory and unemployment picks up.

The latest CoreLogic research shows almost three per cent of properties were sold at a loss in the three months to September, compared with nearly one per cent in the fourth quarter of 2021.

Chief property economist Kelvin Davidson expects the decline to accelerate.

"Historically we've seen 20-25 per cent of re-sales made for a loss, so that sets a bar for where we could be headed."

Sellers are also facing bigger losses or smaller gains as the downturn deepened.

The softer performance of property re-sales in the third quarter is evident across most parts of the country.

"You'd have to think the trend is downward here."

Auckland, Wellington, and Dunedin were showing extra weakness, compared with softening conditions in Hamilton, Tauranga and Christchurch.

Auckland's share of profit-making re-sales reduced by 2.6 percentage points quarter-on-quarter to 94.2 per cent, the lowest figure since the last quarter of 2019. Dunedin's share also reduced by 2.1 percentage points to 96.9 per cent.

It's a long way from the historical peak of sellers taking a loss, he told Morning Report, but "the direction of travel is pretty clear".

Selling costs are still high, bridging finance is still difficult and conditional offers are more common, contributing to a slowing of the market, says Davidson.

However, most vendors are still getting a price well above what they originally paid - ranging from a gross profit of more than $400,000 in Tauranga, Auckland, and Wellington, about $368,000 in Hamilton, and $300,000 or less in Dunedin and Christchurch.

The median resale figure for the properties sold at a gain dropped to $331,000 - well back from the peak of $440,000 in the last quarter of 2021.

"It's important to note that for owner occupiers these aren't necessarily windfall gains. After all, their next property will have gone up in value over time too, with their fresh equity just having to be recycled into that next purchase."

People who had owned and held on to their home for a seven-to-eight-year period should still be sitting on large capital gains.

But others who had bought at the peak of the market and are forced to sell through changing circumstances will be caught out.

"In some cases they will have no choice but to sell at a loss," Davidson says.

-RNZ.