New Zealand Oil & Gas says drilling in the Matuku prospect off Taranaki is likely to begin in mid-September.
The company says the well is expected to take 40 days to drill to a target depth of 4,756 metres.
The permit's operator and 65% owner, OMV, estimates the mean recoverable resource for the prospect is about 65 million barrels of oil.
NZ Oil & Gas owns 12.5% of the prospect. If drilling at the Matuku prospect is successful, it has an option to buy another 5% from 22.5% owner Octanex.