Latest credit card data shows consumers are remaining cautious about spending, as the country emerges from a long recession.
Reserve Bank statistics shows credit card billings fell a seasonally-adjusted 1.3% in December.
BNZ senior economist Craig Ebert says it was a fairly clear drop, which reverses increases seen in the last two months.
Official data issued earlier this month seasonally-adjusted retail sales in November climbed 0.8% to $5.5 billion.
