Higher prices for groceries, fruit and vegetables pushed up the price of food by 0.7% in September.
Statistics New Zealand figures show prices for grocery food rose 1.2% during the month.
They were led by an 8% rise in snack food, a 5% increase in the price of chocolate and a similar rise for yoghurt.
Fruit and vegetable prices rose by 2.6% as unusually windy, wet and cold weather boosted the price of broccoli by almost 50% and lettuce by 14%.
Prices for meat, poultry and fish fell 1%, with fresh chicken falling by almost 8% and lamb chops by 6%.
Food prices are 1.3% higher than they were in September last year.