The National Transport Authority says the three millionth Leap Card has been sold.
The card can be used to pay for public transport services in Dublin, Cork, Galway, Limerick, Waterford and Wexford.
Of the three million cards issued, close to 250,000 have been sold in the first four months this year.
Since the sale of the first edition over six years ago, the card has seen 495 million journeys - 63.5 million of which took place from January to April 2018.
A person scans a Leap Card on public transport | Image via @LeapCard on Twitter
Overall the scheme has reached monthly turnover of €23.3m per month - or over €633m since its launch.
NTA CEO Anne Graham said: "In looking to the future of transport in Ireland, the Leap Card will play an increasingly important role.
"Under the BusConnects strategy unveiled last year, the NTA has committed to simplifying and streamlining the payment process for bus fares for example.
"As part of this process, cashless operation will be introduced on all buses with Leap card becoming the preferred alternative."