ASB Bank has cancelled all pre-approvals for home loans over the 80 per cent loan to value ratio with effect from October 4.
A spokesman for the bank said it had been telling customers and mortgages brokers about the change over the last few days.
The change comes ahead of the Reserve Bank's crack down on low equity or low deposit lending. From October 1 banks must cap new lending above the 80 per cent threshold to 10 per cent or face losing their license.
Shaun Drylie, general manager, product and strategy at the ASB Bank said the change was being implemented to comply with the new lending restrictions.
"ASB, like all New Zealand banks, has to comply with these restrictions under our conditions of registration."