The increase was particularly pronounced in Whanganui-Manawatu, Marlborough, Nelson, Northland, Southland, Tasman, Wellington and the West Coast, with volumes rising more than 20 per cent.
In sharp contrast, volumes fell 5 per cent in Auckland.
Westpac NZ chief executive David McLean said it was heartening to see first home buyers finding places to put down roots.
"The housing market has slowed and that's good for New Zealand. We need a sustained
period of flatter prices so that, as incomes grow, houses become more affordable.
"In many places we're seeing a welcome increase in young New Zealanders getting a foothold on the housing ladder.
"It's pleasing to see plenty of activity in the regions, which are the engine room of the New Zealand economy.
"In Whanganui-Manawatu, for example, mortgages issued by Westpac to first home buyers rose 26 per cent, while Northland had a 44 per cent increase.
"Marlborough had a whopping 74 per cent increase."
In the Capital, Westpac mortgages issued to first home buyers rose 43 per cent - "These figures show buyers are flocking to Wellington," Mr McLean said.
"It's a different story in Auckland, where entering the market is still a challenge for many people.
"Having said that, analysts have noted a recent cooling in prices, meaning some first home buyers may now be reviewing their options in our largest city."
Mr McLean said the Reserve Bank's more-restrictive loan-to-value ratio rules for property investors appeared to have given first home buyers more room to make purchasing decisions.
