Optus' 4G customer base hit 3.18 million in the quarter ending 31 December, the telco revealed this morning.
Optus added 435,000 4G customers in the quarter, amid a decline in overall mobile subscriber numbers.
"The release of 700MHz spectrum on 1 January 2015 is a major milestone in our network expansion strategy, taking us one step closer to our goal to deliver Optus' superfast 4G Plus network to 90 per cent of Australians by April 2015," Optus CEO Allen Lew said in a statement
Data revenues increased 12 per cent, the telco said.
The take-up of 4G and higher data usage was reflected in a higher average mobile revenue per user.
Mobile ARPU increased 5 per cent compared to the same quarter last year, the telco said.
The total number of Optus mobile customers declined by 12,000 compared to the quarter ending 30 September, down to 9.391 million.
The number of postpaid and prepaid mobile subscribers grew, but mobile broadband subscribers declined.
Optus mobile service revenue hit $1.22 billion (up 4.3 per cent).
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Overall, Optus reported a 6 per cent increase in operating revenue to $2.29 billion but an 8.2 per cent drop in net profit to $208 million compared to the quarter ending December 2013.
Optus' owner, Singtel, reported net profit of S$970 million for the quarter, up 11 per cent.
"Optus' second consecutive quarter of revenue and mobile handset customer growth reflects the strength of our core business," Lew said.
"Our strategy to achieve long-term sustainable growth by continual customer service improvements and delivering innovative products and services such as data sharing and Cash by Optus is on track."
"In Singapore and Australia, we proactively acquired and recontracted customers on the back of smartphone launches and successfully upgraded them to higher tiered data plans," Singtel Group CEO Chua Sock Koong said in a statement.
"The regional mobile associates also saw significant take-up of mobile data with higher smartphone penetration."