Telstra is experiencing strong growth in its September quarter, adding more mobile and fixed-line broadband customers, according to the telco's CEO, David Thodey.

He was speaking at company's Investor Update event in Sydney.

Telstra has ramped up its efforts into customer satisfaction over the last year. They include consolidating its sales teams, introducing an easier billing system and major network investments including the release of its 4G LTE network.

According to Thodey, the effort into improving customer service is paying off.

"Importantly, we are adding those new customers profitably and without sacrificing average revenues per customer [ARPU]," he said.

Making customers happy not only inspires word-of-mouth marketing, reducing calls to call centres also saves money for the company since every call has an associated cost.

Telstra has reported 28 per cent of calls to call centre.

The telco is also conscious of the importance of staff believing in the company as a starting point to changing customer opinion of the company.

Thodey said Telstra is keen to make cultural changes within the company.

"If we don't get it right, our company can't be flexible," he said.

Along with reducing incoming calls to call centres, the company has also recorded 51 per cent less ordering errors requiring manual intervention, 34 per cent repeat visits to fix customer problems and 70 per cent more self-service transactions through Telstra's online portal.

"These and other similar initiatives generated $622 million in productivity benefits in fiscal 2011 and are expected to deliver an even greater benefit in fiscal 2012," according to Telstra in a statement.

Taking the progress into account, Thodey said the company is on-track to hit its financial year 2012 guidance of low single digit percent growth in total revenue and earnings before interest, tax, depreciation and amortisation (EBITDA) though the poor performance of Sensis, Telstra's advertising and directories arm, may drag results down slightly.