The estimated effect of Storm Éowyn on phone users is the largest in recording history, according to the Commission for Communications Regulation.
However, Comreg added the impact has appeared to have peaked.
A spokesperson says a total of 40 per cent of all phone users in Ireland are affected by outages caused by Storm Éowyn.
Operators have indicated the most impacted areas are Galway, Donegal, Mayo, Roscommon, Clare, Meath, Dublin, Kildare, Louth, Laois, Sligo and Westmeath.
(photo credit to Newstalk)