Ryanair and Aer Lingus have won a court challenge against an EU ruling ordering the airlines to repay money to the State.
The European Commission ruled in 2012 that the airlines had benefited from illegal state aid by paying a lower levy for domestic flights between 2009 and 2011, but that decision was quashed yesterday by the EU's General Court.
Ryanair said it will now get €12m back while Aer Lingus calculated the money owed at €4m and interest.
Aer Arann is also set to benefit from the decision.
The Government subsequently modified its air travel tax to a flat rate for all flights, domestic and international, in 2011 following the probe.