The reduced VAT rate for tourism, hospitality and some other services returned to 13.5 per cent at midnight.
The Restaurant Association of Ireland said the move by the Government to increase the 9 per cent VAT rate will result in thousands of job losses in the sector.
Advertisement
It means Ireland will now have the third-highest hospitality VAT rate in Europe.
Aisling Kelly, who owns Sligo Oyster Experience, described the decision as "madness".
It's just wrong.
Ms Kelly told Newstalk: "“I think it’s madness, to be honest. Because even the Government will see my Revenue returns, how businesses are doing, and they’re blaming a few hotels that are doing well and basing it on the rest of the country.
"It's just wrong."