More than 50,000 people have subscribed to the new integrated ticket for bus, rail, DART and Luas services in Dublin since it was launched eight weeks ago.
The latest figures show that more than 615,000 journeys have also been taken using the Leap card.
Minister of State with responsibility for Public and Commuter Transport Alan Kelly said the project had surpassed its targets at this stage.
However, the National Transport Authority has accepted there are some issues, particularly in relation to the topping up of the cards, which it is hoping to resolve shortly.
NTA project director Tim Gaston said it is planning to introduce an instant top-up system using direct debits, which will help deal with concerns.
Vending machines at railway stations will also sell Leap cards shortly. Customers will soon be able to top-up at vending machines at railway stations.
The Leap card was finally launched last December ten years after it was first announced. The final cost is expected to be €55m.
The system will be expanded to private and Bus Éireann services in the greater Dublin area later this year. A student Leap card will also be introduced in the summer.
