Rental website Airbnb says its operation was worth over €700m to the Irish economy last year.
This is a combination of host income and guest spending - which globally exceeded €86bn across 30 countries, according to new data released by the firm.
Ireland is at number 20 on a league table of Airbnb countries, based on host income and estimated guest spending.
The USA, France, Spain, Italy and the UK make up the top five.
Almost 1.8 million visitors to Ireland last year used Airbnb for some, or all, of their visit here.
Travellers who stayed with Airbnb spent an estimated €537m in Ireland during their trip - or €116 on average per day.
The majority of overseas visitors to Ireland arrived from the US - followed by Britain, France and Germany.
Hosts in Ireland also saw a boost to their income, collectively earning €168m.
Most popular destinations
The data reveals the most popular destinations for visitors outside the main urban centres.
Based on visitor numbers in 2018, the top five destinations in Ireland for Airbnb guests are Killarney, Dingle, Westport, Tralee and Kilkenny.
Jean Hoey, public policy lead for Ireland, says: "Airbnb has transformed the way people travel, helping visitors to stay and explore in Ireland beyond the traditional destinations and hotspots.
"Our community of hosts and guests is helping to spread the benefits of domestic and overseas tourism and putting money in the pockets of local families, businesses and communities.
"With new regulations coming into effect... we are continuing to work with our host community to help them understand and comply with the new rules."
New short-term letting regulations came into force from Monday.
The new rules mean that planning permission will be required for the short-term letting of properties that are not the landlord's principal private residence.
But property owners will still be able offer rooms within their own homes for short-term stays year round.
In response to the changes, Airbnb says: ""We are continuing our work with hosts to help them understand and comply with the new regulations.
"We remain concerned that hosts have not had sufficient information and time to adapt, and that visitors to Ireland may be negatively impacted.
"We hope to work together with the government on this important effort and are continuing our discussions."