Three is to invest €65 million in an overhaul of its technology platform, including its billing system and other functions, and in the integration of its systems with the business that previously operated as O2 Ireland, which Three bought in 2014.

Three, the State's second-largest mobile operator, has signed a five-year contract with US-headquartered Amdocs to oversee the revamp.

The company said the investment was in addition to a previously-announced €300 million network upgrade to deliver 4G to its customer base of two million subscribers.

Amdocs will seek to integrate Three and O2 customers onto the same billing platform, and will also look to eliminate duplications in their respective systems and processes.

The company said the investment would also allow the delivery of “personalised omnichannel experiences and innovative offerings and rate plans”. Three and O2 customers were on different rate cards when the two businesses merged.

Robert Finnegan, the chief executive of Three, said the Amdocs upgrade will also "substantially" reduce its annual IT costs, which should benefit consumers with lower prices.

Usage habits

The changes will also give Three a better ability to capture information about the usage habits of its customers.

“We will be able to better understand customer behaviour. It will give us a better view of what is happening in the business, and that will benefit customers,” said Mr Finnegan.

He said it would use the behaviour data with consumers’ consent to make sure they were on the best package.

The company said it had “delivered on promises” made at the time of the O2 acquisition, such as facilitating two new entrants to the market using its network on MVNO agreements.

“All of these investments have been made possible by the European Commission’s approval of the deal,” Mr Finnegan said.