Retail spending has risen, led by sales of fuel, cars and hardware.
Statistics New Zealand figures show seasonally adjusted retail sales rose 1.7% to nearly $18 billion in the last three months of 2012.
Such spending had been restrained in recent years, following subdued economic growth and higher unemployment.
But some of that caution appears to have receded, with Statistics New Zealand saying sales volumes recorded their strongest quarterly increase in six years, rising 2.1%. The increase was led by fuel purchases.
Core retail volumes, which exclude volatile fuel and car sales, rose 1.5%, boosted by hardware and building sales in Canterbury.
Economists say the stronger than expected rise in sales offset a sharp decline in the prevous quarter, and indicates retail spending accelerated modestly.
The New Zealand dollar rose after release of the figures on Friday morning, breaking US85 cents.