The number of new cars sold in September jumped by 17 per cent to 3,257, compared to the same month last year, according to new figures from the Central Statistics Office.
However, the overall amount of newly licensed cars on Irish roads is down 7 per cent so far this year.
In total, there were 66,570 new private cars licensed in the year to the end of September 2013, compared to 71,619 in the same period last year.
The number of new goods vehicles licensed in September was 972, up 33.3 per cent from September 2012.
In the private car category, 2,465 licences were for diesel vehicles while 735 were petrol in September.
The number of second-hand vehicles imported into Ireland increased by 32.1 per cent to 37,437 in the year to the end of September.
The total number of used (imported) private cars licensed was 4,735 last month compared with 2,967 during September 2012, an increase of 59.6 per cent.
Volkswagen was the most popular new car on the road in September, followed by BMW, Toyota, and Skoda.