The William Hill bookmaking chain is to close 20 of its shops in the Republic, threatening the future of 85 jobs.
Another 51 shops, including some in the North, are unaffected by the closures.
Staff in Dublin, Cork, Limerick, Tralee and Wexford have been informed and a two-month consultation process will begin in the new year, according to a company statement.
Full support will be given to the staff affected and alternative employment will be offered wherever possible, the company said.
It added: “The shops selected for closure have not been trading profitably for some time, in spite of efforts made by William Hill to return these shops to profitability.
“Whilst the Republic of Ireland Government did not raise betting tax in the recent Budget, neither did it create a climate for growth. This, coupled with the slow progress of the Ministry of Justice review into modernising the gambling regime and the severe economic downturn in the Republic of Ireland, has left William Hill with no alternative but to make closures.
“There are no implications for the wider William Hill estate in Ireland or Britain, although the profitability of individual shops is kept under constant review.”