Irish Rail's fare structure is unnecessarily complex, it is extremely hard to even determine the correct fare in advance as few of the details are available in public, and even then there is a good chance that Irish Rail don't know themselves what the fare is. The scale of the inconsistencies is shocking.
Rail Users Ireland has prepared a list of tips to help you get the best value.
Taxsaver Tickets
Monthly and annual tickets are available through the taxsaver scheme where you do not pay PAYE or PRSI on the value of the ticket. Savings of up to 52% are possible depending on your income and tax status. Monthly and annual tickets are available between any two named intercity stations. Zonal tickets are available in Dublin. The price of an annual ticket is set at 10 times the price of monthly ticket. Further details www.taxsaver.ie.
Off Peak
Travelling outside peak hours outside the Dublin suburban area may lead to a discounted fare. Discounted day return tickets are available from most intercity stations to Dublin and from most stations in Munster to Cork and Limerick. Special discounted fares apply after 9:30am at most stations in the extended Dublin Commuter belt Monday-Friday.
Students
For weekly and monthly tickets within Dublin short hop zone and the Cork Suburban area and for all single/return/weekly/monthly tickets elsewhere. You must have a valid leap student travelcard, or a valid recognised student ID card which must be valid. Discounts vary but can be very significant depending on the journey. The cost of the leap student travel card can normally be recovered in savings within two intercity journeys.
Buy Online
For long distance intercity journeys buying online guarantees the cheapest price while offering the additional value of a reserved seat. Fares start from 9.99 euro on some intercity routes. For more details see here.
As online tickets are also a reservation, you are entitled to additional rights under the Irish Rail passenger charter. If you book first class and no first class is available or you end up standing, or you are transferred onto a different service you are entitled to a full refund
Seek Refunds
If you are delayed or services or facilities on the train don't match with what you have paid for, you may be entitled to a refund. Cross border tickets must be refunded in cash if so requested under EU law.
Further details on claiming refunds here.
Luas / 90 Add On
If you are arriving into Dublin Heuston or Dublin Connolly and wish to travel on the 90/145 bus or the central zone of the Red Luas line, ask for a ticket to 'Dublin City Centre'. This option is also available online.