Luas saw the largest growth, followed by Iarnród Éireann
The number of people taking public transport increased by 3.6% last year.
The National Transport Authority (NTA) says the Luas and Iarnród Éireann saw numbers rise by 6.1% and 5.3% respectively.
It found that all operators saw passenger numbers grow in 2015, with Dublin Bus figures up by 2.8%.
Luas saw the largest growth to 34.6 million passengers, followed by Iarnród Éireann to 39.8 million.
Bus Éireann services saw growth up by 1.7% to 30.2 million passengers for their subsidised services.
NTA CEO Anne Graham said: "These are strong growth figures for the sector, and the operators and their staff should be proud of their achievements".
She added that 2016 would be another busy year for the NTA, with a focus on delivery.
"The Luas Cross City project will be a major focus for us in this current year, managing major construction works through the heart of Dublin while keeping the city open for business".
"We will be progressing our open-market tendering for 10% of the Dublin and national bus routes, opening the Phoenix Park tunnel to passenger trains to bring new routes to people travelling into Dublin from Kildare, and we will be closely examining and improving bus and rail services, and bringing new bus fleet vehicles, in Dublin and throughout Ireland", she added.
She told Newstalk Lunchtime the high numbers are due to a number of factors, saying that it was a combination of a growth in the economy, as well as an increase in the amount of people visiting the country.
When asked about the increase in fares for transport services, Graham said "prices have gone up because we're offering additional services. Because the numbers are up, we've had to run additional buses, and we will, in the future, be operating additional services, so the cost of that does go up because you have additional staff involved in the production of services".
However, she added that "in this year, for some of Bus Eireann's customers, as well as Dublin Bus cash customers, there is a reduction in fares in 2016. In looking at fares, we would also propose [...] a fairer, more distance-based fare structure".