Iarnród Éireann says it will now work with Bus Éireann to establish the replacement bus schedule.
The company says it will confirm as soon as possible the date on which rail services will be suspended but it is expected that this transition will be completed during September.
The board of the NTA met today to discuss Iarnród Éireann's controversial proposal to suspend the service.
The rail line has been carrying passengers for over 105 years.
One train goes from Rosslare to Waterford at 7am, with one train back in the evening.
Campaigners say the service is totally inadequate and has led to the line being under-utilised.
Iarnród Éireann says the route is no longer economically viable, is losing money, attracts only about 25 passengers a day and has lost most of its freight business.
However, business leaders, local authorities and campaigners in the southeast have been campaigning for its retention and an enhanced timetable with extra services.
A group of more than 50 politicians, including Fianna Fáil TDs, Green Party Senator Dan Boyle and Opposition TDs and Councillors, gathered in Waterford this week demanding the line be kept open.
