Mobile phone company mmO2, parent of Irish operator O2, gained almost 300,000 new customers in the three months to June 30th but lost almost 2 per cent of its Irish customer base, with its prepay operations witnessing a significant fall-off in user numbers.

The Republic was the only state in the company's four-country operation where overall user numbers fell in the quarter but the average revenue per user (ARPU) rose, as did the number of people using more lucrative postpay mobile phones.

Overall, the mmO2 group saw customer numbers increase by 292,000 to 17.46 million, with 86 per cent of new users opting for billing services. Across its operations in the Netherlands, Germany, Britain and the Republic, the company has 11.3 million prepay customers and 6.1 million billing customers. However, while overall customer numbers rose in all other markets, numbers in the Republic fell. Some 22,000 customers left the prepay operations in the State with 3,000 new users signing up for the billing service, leaving a net fall-off of 19,000 customers in the quarter from an Irish customer base of 1.2 million.

Ms Johanna Cassells, a spokeswoman for O<2, said the fall-off in numbers in the State was not a concern for the firm, saying the prepay market was fickle as customers change operators from quarter to quarter depending on which operators offer the best deals. "If you lose 22,000 in one quarter, you tend to gain them back in the next. But if you look at postpay, we have gained 3,000 in three months and we are very pleased with that," she said.

On average, ARPU in the Republic rose by 3.5 per cent compared with the previous quarter.