Holders of child Leap cards will be entitled to free travel on Dublin Bus, Luas, DART, short-hop commuter rail in Dublin and Bus Eireann city services in Dublin and surrounding counties, Cork, Limerick, Galway and Waterford.
A number of private operators will also provide free travel in Wexford and Ashbourne, among other areas.
The scheme is designed to encourage families and children to use public transport for their leisure activities in the school holidays.
It is also designed to highlight the cheaper fares offered by Leap, which are typically between 15pc and 20pc cheaper than paying by cash.
Transport Minister Paschal Donohoe said the one million Leap cards had been sold.
“This initiative will further promote the scheme and encourage greater pick-up by commuters,” he said.
“More than that, it rewards Leap Card users, giving them a valuable incentive they will feel in their pocket, at a time when they are out and about enjoying what we hope will be July summer sun.”
Anne Graham, CEO of the National Transport Authority said it was the second year of the ‘Kids Go Free’ promotion, and that demand should be stronger than last year as the Leap card was now available in more locations.
“We are particularly keen that those in the senior cycle of secondary school apply for their personalised card so that they can enjoy the cheapest fares for getting to and from school, and for their extra-curricular activities,” she added.
Full details on where to get a Child Leap card, including identification requirements for older teens, are available at www.childleapcard.ie.