The number of new cars licensed last month was more than double the level recorded in September 2009, according to figures from the Central Statistics Office (CSO).
There were 4,683 new private cars licensed (taxed) in September, compared with 2,272 in September of last year, representing a year on year increase of 106.1 per cent.
However, the number of new goods vehicles licensed in September fell by 13.6 per cent to 671, down from 777 in the same month last year.
The CSO said there was a 62.8 per cent increase in the number of vehicles licensed overall from 3,583 in September 2009 to 5,802 last month.
In terms of model, the most popular new private cars licensed in September were Renault (752), Toyota (681), Volkswagen (479), Ford (432) and Opel (319)
Some 2,997 of the new vehicles registered were diesel, 64 per cent, while 1,405 were petrol (30 per cent).