E-tickets will be available on all inter-city Irish Rail services from Tuesday.
Passengers who book online or through the Irish Rail app or website will now be emailed a barcode that can be scanned at barriers.
Customers still have the option to print their tickets at machines in the station if they wish, but can also use their phones or email to scan the barcode directly.
There'll be no change to the price of tickets, and no extra charge for the e-ticket feature.
Until now, e-tickets have only been available on semi-flexible or low fare journeys, but they're now being extended to all fares across inter-city journeys in the state.
Irish Rail's Corporate Communications Manager, Barry Kenny, announced the news this morning, saying made the "sustainable” decision and will prevent “millions” of paper tickets being printed.
“It will also provide greater flexibility for customers in terms of being able to change return legs of journeys,” he said.
“This is a way to offer customers more convenience.”
Mr Kenny confirmed no changes will be made to Irish Rail intracity DART and commuter services.
The new e-tickets also won't affect Leap Card journeys, and are only available for purchases that can be made online.