Irish phone and mobile service revenues fell by €120m in the last 12 months - one of the sharpest declines in years.
The fall is due to lower average mobile revenue figures, price caps on services such as roaming and a further decline in SMS texting and landline calls.
The figure is contained in the latest quarterly report from telecoms regulator Comreg.
Despite falling by 1.4pc, Eircom remains the biggest fixed line broadband provider with 36.5pc of the market. UPC is second with 28.9pc while Vodafone is third with 17.2pc. Sky has grown by half to take 7.4pc of the fixed broadband market, while smaller players such as Imagine have fallen.
In the mobile market, Vodafone remains the biggest operator with 39pc of the market despite losing 1.6pc of the Irish market in the last 12 months.
3 Ireland is the second largest mobile operator, with 32.1pc, marginally more than the combined O2 and 3 Ireland subscription base of 12 months ago. Meteor has 21pc, slightly up on a year ago, while Tesco Mobile climbed from 4.3pc to 6pc.
When mobile broadband and machine-to-machine connections are included, Vodafone (38.5pc) and 3 Ireland (35.8pc) are closer in size. However, both operators have lost market share, according to this metric.
Comreg's report says 65pc of Irish homes and businesses now have a fixed broadband connection, either landline or cable. Nearly half have broadband speeds of over 30Mbs, a jump of 20pc in the last year, while almost two-thirds have speeds of over 10Mbs.
Around 11pc of Irish mobile phones are now using 4G while mobile SMS messaging fell by 12pc over the last 12 months. Mobile data usage almost doubled.
There are now 5.8m mobile subscriptions in the country, but mobile broadband subscriptions, which connect dongles and mifi devices to cellular networks, fell by 13.4pc to 433,000.
The average revenue per user continues to fall, from €26 per month to €25. The number of prepaid users fell compared to 'contract' users, as high-end phones came on the market with operator subsidies for contracts.