Eir's SIM-only mobile service GoMo has said that from today, all of its new customers will get all calls, all texts and all data for €12.99 a month - for life.
The mobile brand launched in October and over 100,000 customers have signed up to its introductory offer of all calls, all texts and all data for life for €9.99 a month.
The company said it had exceeded the 100,000 cut-off by Christmas and ended its €9.99 offer on January 8.
GoMo said today's offer will be available for a limited time and only customers who join on or before March 1 2020 will be guaranteed the offer.
The no-frills service offers a SIM-only option and has not shops or other physical presence, instead offering its customer services over the internet.
SIMs are sent by courier to the address of the customer.
It uses Eir's network and offers 99% population coverage and over 97% 4G coverage.
The offering has proven extremely popular with customers, triggering competitive pressure in the mobile market.
Meanwhile, the Advertising Standards Authority for Ireland is investigating GoMo over its promise to provide early subscribers with a fixed deal "for life".
The Irish Times reports that complaints have been lodged with the ASAI over the offer.
The complaints arise because of GoMo's terms and conditions which make it clear that the company reserves the right to amend prices at any time.
ComReg also said last month that it had received "a large number" of complaints about GoMo.