ANZ New Zealand's profit has jumped 18 per cent to 930 million - for the half-year to March

The country's largest bank's cash profit has also risen 42 per cent to 962 million -- after making a significant reduction in credit impairment charges and a strong home lending market.

Chief executive officer Antonia Watson says the full impact of Covid-19 on the New Zealand economy had yet to play out.

But she says sectors such as housing, construction and agriculture have proven resilient during the crisis.

Westpac's New Zealand arm reported a doubling in cash earnings over the same period, also due to better than expected economic conditions.