NZ consumers opened up their wallets going into winter, with big spending on building and garden products.
The latest official figures show the volume of retail sales, which takes account of price movements, rose by 2.3 percent in the June quarter, the biggest gain in nine and a half years.
That compares with a 1 percent rise in the previous quarter.
Statistics New Zealand said spending on do-it-yourself and home improvement products led the surge, with solid increases in sales of vehicles and pharmaceutical and personal products, as well as a rise in spending on eating and drinking out.
The total value of retail rose by a record 2.2 percent during the quarter, to just below $20 billion.
Westpac senior economist Satish Ranchhod said consumers were benefiting from several positive factors.
"We've got low interest rates and low inflation, and those factors are putting money back into household's pockets. But there are also more people in the economy, there has been strong migration and a strong tourist season, and that means more bodies in stores, helping to boost these spending figures."
Mr Ranchhod said the downside of the spending boom was that consumers were increasing their debt, which was not sustainable.