Ryanair will allow passengers on services from Dublin to use their mobile phones in-flight from July.
Technology that directs mobile signals via a satellite will be fitted on 14 aircraft in a trial. Mobile use will remain banned on other flights because the signals interfere with aircraft control systems.
Up to six passengers will be able to hold phone conversations at once. A Ryanair spokeswoman said guidelines had yet to be finalised, but passengers would not be allowed to use phones during take off and landing.
The carrier will take a slice of the international call rate. It plans to allow mobile use on 50 aircraft by March 2009.