Telstra has delivered its first increase in annual profits in three years after adding 1.6 million customers to its mobile network.
Telstra reported net profit after tax of $3.4 billion for 2011/12 on Thursday, an increase of 5.4 per cent on the previous year, and announced its mobile customer base now stands at 13.8 million subscribers.
Mobile customers now account for one third of Telstra's revenue, which was up 1.1 per cent to $25.4 billion for 2011/12.
Among those mobile customers are 375,000 subscribers added to Telstra's 4G network since it launched in September, 2011.
Telstra chief executive David Thodey said the strong growth in mobile over the past two years - in which Telstra has won three million customers - was unlikely to be as strong in 2013.
However the forthcoming launch of the new Apple iPhone 5 - tipped to happen in September - is expected to be "a jab in the arm" for the industry.
Australians continue to abandon landline telephones, with a decline of 281,000 in Telstra fixed-line customers over the year to 6.9 million, and fixed-line revenue falling 10 per cent to $4.8 billion.
Fixed-line broadband customers grew by 200,000 to 2.6 million.
Telstra chief financial officer Andy Penn cited research showing two per cent of households became mobile-only during the year, taking the national total to 14 per cent of households.
Mr Thodey did not directly answer a question on whether the trend to mobile-only households had implications for the National Broadband Network (NBN) but said: "These are just trends that we have factored into our businesses going forward".
He said the six-month delay to completion of the NBN, revealed on Wednesday, would have no material impact on Telstra's revenue guidance.
Telstra's earnings before interest, tax, depreciation and amortisation (EBITDA) were $10.23 billion, slightly lower than analysts' expectations.
Cameron Securities adviser Henry Jennings said the profit result came in slightly below expectations and fed some profit-taking as investors favoured higher-risk stocks on positive news from Europe.
"(The results are) a little bit disappointing but it's not the end of the world. It's not a huge miss," Mr Jennings said.
Telstra shares were 7.5 cents, or two per cent, lower at $3.895 at 1254 AEST.