Passenger numbers on Luas services in Dublin increased last year by approximately 300,000 on the 2011 figures.
Provisional figures indicate that 29.4 million passenger journeys were made in 2012, the highest ever level.
The busiest periods were at the end of August, during the Tall Ships Festival, and during the Christmas season in December.
A Luas extension linking the Red and Green lines, due in 2017, is expected to generate an extra 10 million passenger journeys in a full year.
Railway Procurement Agency Chief Executive Rory O'Connor said it was gratifying that Luas continued to operate successfully without any public subvention.
He said the strong performance last year underpins Government support for the new extension.