The Irish Aviation Authority has reported a 85% fall in the number of flights handled in April compared to the same time last year as Covid-19 grounded most airline fleets around the world.
The IAA said that Dublin airport recorded 2,067 flights, an 89.8%% decrease on the same time last year.
Cork airport traffic saw just 225 movements, down 93.9% on the same time last year, while Shannon airport reported 364 flights, a 79.8% decrease on April 2019.
April also saw a decrease of 81.8% in Ireland's overflight traffic movements - flights that do not land in Ireland - to 5,279 from 29,077 in 2019.
IAA's chief executive Peter Kearney said that while the collapse in air traffic levels has been swift and sudden, the IAA is hopeful that the decline has reached the bottom and attention can now turn to re-opening aviation in Ireland's interest.
"As an island economy, Ireland is reliant on aviation for economic growth and prosperity. Aviation is an economic enabler and Ireland has become a major global player in the aviation sector. It is important therefore, if Ireland is to recover from the Covid-19 pandemic and return to growth, that we have a fully functioning and stable aviation industry," Mr Kearney said.