Frankfurt - Dublin DEM 352 Please see the airline's website for availability and restrictions.
All fares quoted above are for round trip tickets.
Online reservation and ticket purchase is available at EasyJet and Ryanair . Ryanair is the most bureaucratic of the two. While virtually any ticketless airline on the planet will accept sight of your credit card or other ID for boarding pass issue, Ryanair often demand presentation of a photo-ID combined with sight of the computer printout of your reservation confirmation. If your trip to Ireland involves a Saturday night stay, it may be just as cheap on a full fare airline such as Aer Lingus, Air France, Lufthansa, Iberia, etc. Check availability on the Ryanair webiste.