The number of foreign residents who arrived into Dublin Airport increased by nearly 66% last week - which was the first full week of mandatory hotel quarantine.
Figures released to Newstalk from the Department of Justice show 8,560 non-Irish residents flew into the capital.
This is an increase of over 3,400 more than the previous week.
The majority of those arriving - 70% - say they were travelling for non-essential reasons.
The number of Irish residents who arrived home from abroad was actually down 19% to 5,545.
In total, 14,105 people flew into Dublin Airport last week - which is up over 17%.
Arriving passengers were asked whether their journey was essential or non-essential.
Between March 30th and April 4th, 12,291 passengers arrived at the airport.
Of these, 3,684 (30%) said they had travelled for an essential reason - and 8,607 (70%) reported they had travelled for non-essential reasons.
However the Department of Justice noted that the categorisation of essential travel was changed since March 30th.
It is now based on an EU Council recommendation.
Essential travel is defined as: "Workers or self-employed persons exercising critical occupations including health care workers, frontier and posted workers".
It also includes transport workers, patients travelling for medical reasons and students who travel abroad.
A category of people "travelling for imperative family or business reasons" is also on the list.
But it does not include, for example, people who have travelled for "pressing personal or humanitarian reasons" - such as the death of a close family member.
Meanwhile 10 residents of mandatory quarantine hotels have tested positive for COVID-19 since the system was introduced.
HSE National Lead for Testing and Tracing, Niamh O'Beirne, said on Thursday that all residents and staff are regularly swabbed.
She said: "To date, 413 people have been swabbed who've come through as residents.
"To date, there have been ten detected cases in the quarantine residents."
Since late last month, arrivals from dozens of countries have had to quarantine in a hotel for two weeks after they arrive in Ireland.
Reporting by: Eoghan Murphy