The Central Statistics Office says that consumer prices rose by 0.7% in August compared to July.
The CSO says that during the month people paid higher average mortgage interest repayments, while the prices of clothing and footwear also rose as the traditional summer sales ended.
Transport costs were also higher due to increases in airfares and car rental charges, but the prices of some food and non-alcoholic drinks fell last month.
Meanwhile, the Small Firms Association has said that the most worrying aspect is that inflation is being driven by increases in public utility costs.
