Two hundred and fifty new jobs have been created in Co Wexford.
Eishtec is opening a new call centre in Drinagh- which will provide support for Orange, T Mobile and EE customers.
The company already employs 400 people in Waterford.
Recruitment for the new positions is already underway.
Eishtec is run by former employees of the Talk Talk call centre, which closed its doors in Waterford in September 2011 with the loss of 575 jobs. The company was set up by Heather Reynolds, Brian Barry and Colm Tracey in May last year with nine employees after the closure of Talk Talk.
The Jobs Minister Richard Bruton has welcomed the announcement, saying the company is creating jobs in a part of the country which has suffered from high levels of unemployment.
“This is an Irish company founded by three former employees of a multinational, winning business in a highly competitive market, and growing employment in a part of the country which has suffered from high levels of unemployment,” he said.
Brian Barry, one of the co-founders of Eishtec, said: “We are particularly encouraged by this growth because in January 2012 we announced 250 jobs for Waterford and, based on delivering strong performance to date, we have been able to grow beyond that figure to 400.”