Annual food prices rose their highest in 13 years, up 8.3 per cent last month compared with August 2021, Stats NZ said today.

That was the largest annual increase since July 2009.

Year on year, fruit and vegetable prices increased 15 per cent. Meat, poultry, and fish were up 7.6 per cent compared to August last year.

Non-alcoholic beverage prices increased 4.1 per cent and restaurant meals and ready-to-eat food prices increased 6.5 per cent.

Food prices also rose more than one per cent compared with last month.

Even after seasonal adjustment, overall food prices were up 0.9 per cent on last month.

Fruit and vegetable prices jumped 4.1 per cent last month, up 2.3 per cent even after seasonal adjustment.

Seasonal adjustment basically took into account the fact some products invariably had price spikes in certain months.

Meat, poultry, and fish prices rose 1.2 per cent last month.

Today's stats followed months of rotten news for consumers.

• Data shows 8.7% increase in costs from grocery suppliers to supermarkets on previous month
• Govt expected to force big supermarket chains to supply rivals

Last month, the StatsNZ data showed fruit and vegetable prices shot up by 10 per cent in just one year.

And food prices overall were 7.4 per cent higher in July this year compared with July 2021.

Back in June, annual food price inflation was 6.8 per cent.

Food prices in the previous 12 months had increased across the board, with fruit and vegetable prices soaring 10 per cent.

Higher dairy prices have at times also been a major contributor to grocery inflation.

Earlier in the year, cheddar cheese, milk and eggs were big contributors to soaring grocery bills.

Some economists in recent weeks have told the Herald inflation had probably peaked.

Data on the country's GDP is due out on Thursday.