The number of people arriving on flights landing at the country's three main airports has decreased sharply since mid-August, with passenger levels down 64pc.
Figures published by the Department of Transport show the weekly number arriving in Dublin, Cork and Shannon has fallen from almost 70,000 in the second week of August to just over 25,200 for the week ending October 25.
Similarly, the number of departing passengers at the airports was down 46pc over the same period - dropping from 54,800 to 29,500 per week.
Shannon was the worst affected, with passenger arrivals down 81pc.
Weekly numbers were down from 2,726 to just 505 in the final week of October, while numbers in Cork were down from over 4,700 to 1,500 for the same period.
Dublin Airport, which handled around 430,000 arrivals per week in August last year, saw numbers fall to 59,600 this year.
Passenger arrivals at Dublin since mid-August have declined by 63pc and fell to just over 23,200 in the last week of October.
The decline has increased since any remaining countries on Ireland's Green List for travel were removed, alongside the imposition of Level 5 restrictions.
Passenger arrivals across the three airports fell by 24pc in the last two weeks of October, with numbers at Shannon down by 51pc.
The figures - which were provided in response to a parliamentary question from Social Democrats co-leader Catherine Murphy - come as the country's Chief Medical Officer Tony Holohan stated he could not yet give advice for people wishing to return home to Ireland for Christmas.
Dr Holohan has told the Oireachtas Transport Committee international travel would represent a prominent risk.
He warned the impact of imported cases becomes greater when there are low levels of domestic transmission. He said this was demonstrated during the summer when travel-related infections accounted for a quarter of all cases.
Separate figures from the Department of Transport show the number of weekly passengers travelling through the ferry ports of Dublin, Rosslare and Cork has fallen by 68pc since mid-August.
Almost 26,700 passengers travelled in the second week of August, but just under 8,500 travelled by the end of October.
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Visitors to Ireland from some regions won’t have to quarantine from Sunday if they can provide valid proof of a negative Covid test taken within three days before they travelled.