Consumer prices in Ireland rose by just 0.2 per cent year-on-year this month compared with 1.1 per cent in August, a flash estimate showed on Monday.
It is the lowest rate since inflation took hold in March 2021 and far below last month's euro zone average of 2.2 per cent.
The prices, as measured by the Harmonised Index of Consumer Prices (HICP), fell by 0.8 per cent month-on-month with energy prices estimated to have decreased by 1.4 per cent in the month and by 14.1 per cent in the 12 months to September.
Ireland had the joint third-lowest rate of inflation in the euro zone last month after inflation reached almost 10 per cent two years ago.
Excluding energy and unprocessed food, the core rate of HICP was 1.8 per cent higher year-on-year in September, data from the Central Statistics Office showed.
The drop to almost zero inflation comes a day before the Government introduces another big package of cost-of-living financial support on top of planned permanent spending increases of 6.9 per cent and tax cuts in its budget for 2025.
Separate data showed that provisional retail sales fell 1.5 per cent month-on-month in August to stand 2.5 per cent lower than a year earlier.
