The two-storey art deco building on the corner of Queen and Russell streets is currently being renovated and the bank plans to open the branch in April 2022.
Westpac's former home in the centre of Hastings is now up for lease through real estate company Bayleys.
Bayleys confirmed it was currently negotiating with parties to lease the building as well as negotiating with a potential buyer.
Bayleys real estate agent Rollo Vavasour said the property had been evaluated by structural engineers and had received an "A-grade" rating.
"We have got reports from several structural engineers who have given the building an A-grade seismic rating."
Westpac New Zealand general manager of consumer banking Gina Dellabarca said they were looking forward to moving into their new premises in Hastings.
"It's a beautiful art deco building which we'll be fitting out with a range of banking facilities for the community.
"It'll be a great new home for our team of banking specialists across consumer, business and agri-banking," she said.
"The team is doing a great job serving their customers out of Havelock North, where we've extended our opening hours, and Napier, but look forward to returning to Hastings when the new branch opens."
A 24-hour lobby in the old building at 103 Heretaunga St in Hastings remains open with a Smart ATM and cash exchange machine.
A sign remains up at the branch pointing clients to their nearest branch in Havelock North.
Westpac has previously stated that the closure of its branch on March 10 was the result of a "building assessment" but had nothing to do with an offshore earthquake and subsequent tsunami warning which happened on the same day as the closure.