The two parties have entered into a non-binding agreement for the sale of the branch, whose portfolio of some 5,900 customer accounts has a value of around US$496.8 million.
Norman Wilson, chief executive officer of HSBC in New Zealand, explained that this sale owes to a change of focus by the bank.
He said: "It is our intention to focus our business on those customers whom we are best placed to serve. In large part, these customers have international interests and need the unique support HSBC can offer.
"Kiwibank is growing its market share in New Zealand and is well placed to provide the customers who came to HSBC through AMP with the quality of products and support to which they are accustomed. HSBC will work with Kiwibank in the future, using our presence worldwide to help it access global capital markets."
The transaction will go through subject to regulatory approval and the agreement of final terms and conditions.