Grocery inflation has reached 9.5%, which Kantar says is the highest level seen since it first started tracking the data in July 2008.
Kantar says food and drink prices are continuing to climb, with consumers paying 8.1% more per item during the month of August than the same time last year.
It says everyday essentials such as, butter, milk, flour, eggs and bread are seeing some of the biggest price rises, meaning the average annual shop could rise by €662 if consumers buy the same products as they did last year.
Spending on branded goods dropped by over 3%, while spending on own-brand products is up by 2.7%.
However, many analysts say shoppers are swapping to cheaper alternatives due to the rising cost of living.
