Chief executive David Hisco said the solid performance was a result of the business being focussed on sustainable growth, increasing productivity across the organisation and delivering digital innovation for customers.

"All our business units performed well in this half due to our continued simplification of the business.

"We've boosted our focus on digital innovation which has positioned us well for a period of rapid change in banking. Adopting to this new digital environment has resulted in record high brand consideration and customer satisfaction.

"We're the only bank in New Zealand to offer ApplePay, which has been taken up by thousands of Kiwis, and this complements our popular goMoney app."

Net interest income increased 3 per cent compared with the March 2016 half, primarily reflecting continued lending growth, while net interest margins have contracted due to increased funding costs and demand for fixed rate home lending.

Hisco said expenses decreased 12 per cent and the increase in other operating income reflected higher markets trading income and valuation gains on derivatives.

"We've retained our number one market share in mortgages, which has been balanced with our commitment to lending responsibly.

"This lending is having a positive role in the lives of our customers, helping people into homes, supporting our farming communities and growing businesses, both big and small.

"Our encouragement to Kiwis to save has pleasingly also gained traction, with growth in customer deposits."