BNZ announced plans to launch a shared ownership scheme in December, and has selected the private finance company as its preferred partner.
The shared ownership scheme echoes models across the globe. Alongside the borrower, YouOwn will take a slice of the equity in a home, which will be gradually paid off over time.
The product is aimed at first home buyers struggling to get on the property ladder as prices continue remain out of reach for younger buyers.
BNZ has previously described the product as "a commercial take on the Bank of Mum and Dad for new home owners".
The pilot programme is expected to launch in the next few weeks, and comes at a time when first home buyers are grabbing a bigger slice of the market.
BNZ chief customer officer Paul Carter said: "We’ve been working to create a unique option for new home owners. YouOwn’s Nigel Spratt already has experience offering shared-ownership options through his previous work with the New Zealand Housing Foundation. He understands intimately how shared-ownership works."