Hotels and B&Bs can welcome back guests for the first time in more than 5 months from today.
Guesthouses and self-catering accommodation can also reopen, as part of the government's planned easing of restrictions.
The Irish Hotels Federation says today's reopening will result in more than 30,000 staff returning to work over summer.
General manager of Montenotte Hotel in Cork City, Brian Bowler, says there's a great sense of excitement at being able to reopen today.
"It's been a really long 6 months, when you think about it the last time we were open to the public was Christmas Eve."
The hotel boss says he's "absolutely thrilled" to reopen and thought the day would never come."
Restaurants Plan To Take Legal Action Over Reopening Date
Meanwhile, restaurants and pubs have to wait until next Monday to resume outdoor services - and they can't serve indoors until July 5th.
The Restaurants Association of Ireland hopes to begin legal action against the state on Friday.
Chief executive Adrian Cummins says they should be opening in line with hotels today.
He's described the later reopening as "unjust and discriminatory".
"We need to challenge this as it will set precedence in the future."
"We want to make that we give a fair and just directive for our industry."
The RAI boss says he wants to see the hospitality sector reopen "in a balanced and professional way".