Verizon Communications announced its sixth consecutive quarter of double-digit percentage growth in operating income, driven in part by a strong performance from its wireless unit.

Revenue at its mobile arm in the second quarter increased 7.5 per cent year-on-year to $21.48 billion, with the service portion of this increasing by 5.9 per cent to $18.08 billion.

Operating income in this unit increased 8.1 per cent to $6.99 billion. Margin increased to 32.5 per cent from 32.4 per cent.

The company ended the period with 104.64 million wireless connections, of which 98.59 million were retail contract customers. It added 1.44 million customers in this lucrative segment during the quarter.

It saw a small drop in retail prepaid subscribers of 14,000.

It also picked up 2.3 million 4G contract subscribers, including 1 million smartphones and 1.2 million tablets.

Retail contract average revenue per account was $159.73, up 4.7 per cent year-on-year, but essentially flat from the prior quarter following the introduction of the operator’s Edge plan.

Smartphones accounted for almost 91 per cent of contract phones activated during the quarter, taking the penetration of such devices among this customer base to 74.6 per cent, up from 64 per cent twelve months ago.

On a group level, the company reported an operating profit of $7.69 billion, up 17.2 per cent, on revenue of $31.48 million, up 5.7 per cent. Net income was $4.32 billion, down from $5.2 billion.

Reflecting the change of ownership of the Wireless unit, formerly a joint venture with Vodafone Group, net income attributable to Verizon increased to $4.21 billion, up from $2.25 billion.

In its fixed operation, Verizon reported an operating profit of $259 million, compared with a prior-year figure of $74 million, on revenue that was flat at $9.76 billion.

During the second quarter, Verizon Wireless continued to add capacity to its LTE network, using its AWS spectrum. Called XLTE, the feature is now available in more than 350 markets.