Growth in the country's services sector slipped slightly in February but remained close to January's post-Brexit high and confidence about the future continued to grow.
Ireland is widely considered the European Union economy most at risk from the Brexit decision.
Growth slowed in both the services and manufacturing sectors after the surprise referendum result.
The Investec Services Purchasing Managers' Index slipped to 60.6 in February from the seven-month high of 61 in January, as growth in prices charged slowed, but new export business improved.
"While the rate of growth in activity across much of Ireland's private sector has eased slightly from January, it remains well above the series average," Investec Ireland's chief economist Philip O'Sullivan said.
"Firms remain very optimistic on the outlook for the sector," he added.
The services sector has not fallen below the 50 mark that separates growth from contraction since June 2012. The economy has since recovered to be the best performing in the EU.
Today's survey shows that the new export business sub-index climbed to 58.4 from 56.1, the highest rate since July.
The survey showed growth increasing slightly in employment levels but slowing in prices charged and in the amount of outstanding business.
A survey on Wednesday showed growth in the manufacturing sector slowed in February despite exports getting a boost from improved demand in Britain as sharply rising input costs dented profit margins.
The services sector covers areas as diverse as communication, financial and business services, IT and the tourism trade.