Auckland's average house price broke through the $600,000 ceiling for the first time last month.
Barfoot & Thompson says the average price of almost $619,000 was an increase of $33,000, or 5.6% on the previous month.
The figure is also more than 4% higher than the previous record price of $592,000 recorded in August.
Chief executive Wendy Alexander says she's shocked at the high prices.
"The average sale price has been dramatically influenced - particularly in October - by the number of properties that were sold in excess of $1m," she says.
"We sold 119 properties for in excess of a $1 million in October ... we have sold 763 properties for the first 10 months of 2012 in excess of $1 million".
"There's some very fine properties among them ... but in some suburbs it's quite an ordinary home for over $1 million".
Ms Alexander said the number of houses for sale is the third lowest in a decade and demand is far outstripping supply.