Tourism minister Catherine Martin has announced new rules with the aim of making short-term letting less attractive for landlords.
Online platforms such as Airbnb will be fined up to €5,000 if they advertise lettings which have not been registered with Fáilte Ireland.
Fáilte Ireland will also be able to a levy €300 fixed payment notice on property owners who advertise their property without a valid registration number, with inspectors also having the option to bring the case to the district court, where the maximum fine is €5,000.
Fianna Fáil councillor Niall Kelleher is president of Killarney Chamber of Tourism and Commerce.