House sales volumes are strong for midwinter, particularly the top of the North Island and in Central Otago, the Real Estate Institute says.
The Institute also said there was further evidence Aucklanders were buying outside the city.
The strong demand drove the national median house price up 11 percent to $465,000 in July.
If Auckland is excluded, the median stood at $352,000.
The number of sales rose 38 percent to 8,121 in July, compared with the year before.
Real Estate Institute chief executive Colleen Milne said a lack of stock continued to be a significant problem in Auckland, with less than 10 weeks supply available.
She said there was an emerging problem in other regions as well.
However, she said prices in the metro-Auckland area dipped slightly in July by 2.6 percent, from June.