Aer Lingus and Ryanair have given estimates of how much the disruption to air traffic caused by volcanic ash will cost them.
The disruption has also led to temporary lay-offs at a catering company which operates at the three main Irish airports.
Meanwhile, the Irish Hotels Federation estimates that hotels around the country have lost up to €20m due to cancellations as a result of the disruption.
Ryanair says its net profit for the year to the end of March 2011 could be hit by around €6m a day over the seven days of the flight disruptions between Thursday April 15 and Wednesday April 21.
It says the figure will vary depending on how long the disruptions last. It will give an analysis of the likely total cost in its full-year results announcement on June 1 next.
Read updates on the travel disruption here
Aer Lingus has estimated that the disruption caused by the Icelandic volcano eruption has cost the airline between €15m and €20m. In a statement this morning, it said it was losing €4-5m a day.
However, the airline said it had substantial cash reserves and could withstand a sustained closure of airspace.
It said that substantially all of its flights have been grounded since the morning of last Thursday and since then, about 1,100 flights have been cancelled.
It added that the daily costs over the next few days will depend on the pattern of cancellations and added that it make further announcements as appropriate.
British Airways said yesterday that the ash cloud is costing the group £15-20m sterling a day. Air France has puts cost of disruption at €35m a day, while Scandinavian airline SAS said it had lost up to €29m in just four days of grounded flights.
Aer Lingus shares closed down 2.8% at 70 cent in Dublin, while Ryanair shares ended down 1.7% at €3.83.
Lay-offs at airport food stores 'temporary'
HMSHost, a catering company which employs 200 people at Dublin, Cork and Shannon airports, says the disruption caused by the Icelandic volcano eruption has forced it to temporarily close most of its facilities at Irish airports.
The company said, as a result, some staff had been laid off, but stressed that the lay-offs were temporary.
'We are currently monitoring developments and will be in a position to re-open and re-engage all our current staff on their existing terms and conditions once the situation returns to normal,' the company said.
Ash pressure worries CityJet chief
Meanwhile, the chief executive of CityJet has said that some airlines have taken risks running test flights through volcanic ash plumes.
Speaking on RTE's News at One, Geoffrey O'Byrne-White said that following these test flights, damage had been caused to some aircraft which had flown in proximity to the ash. He said there was no point conducting test flights unless they were carried out by scientific aircraft.
Mr O'Byrne-White said there had been huge commercial pressure on airlines to get back into the air, and he expressed concern that unreasonable pressure was being placed on the regulators to give way to those commercial needs.
He said the regulators and technical experts were dealing with an unprecedented situation and must be given time to determine what the risks are, before aircraft go back to the skies.
The CityJet chief said it was illogical for airlines to fly through 'Visual Flight Rules' conditions. This involves flying by visual means only, without instruments.
