Growth in Kiwibank's mortgage book in the September quarter was the slowest since before the global financial crisis.
As with the major banks, the government-owned bank's lending to those with deposits of less than 20 percent also declined.
Kiwibank lent a net $134 million more in mortgages in the three months ended September, taking its total mortgage book to $13.9 billion.
That figure is down from its $223 million growth in the June quarter. It is also a far cry from the near $900 million increase it recorded in the December quarter of 2008 in the depths of the global financial crisis, when other banks' mortgage lending had slowed to a trickle.
In the latest quarter, Kiwibank's lending to those with less than a 20 percent deposit fell by $114 million.
Such lending accounted for a little below 15 percent of Kiwibank's total mortgage lending at the end of September, down from nearly 19 percent a year earlier when Reserve Bank restrictions on such lending came into force.
Kiwibank's profitability was strong in the latest quarter, rising 34.6 percent to $35 million, reflecting strong growth in net interest income.