File photo: Nadine Hutton.

Johannesburg - Vodacom, the mobile operator with the most subscribers in South Africa, said third-quarter revenue rose as customers outside its home market more than doubled their spending on data.

Sales increased 11 percent to 20.2 billion rand ($1.82 billion) in the three months through December, the Johannesburg-based company said in a statement today.

Data revenue gained 41 percent to 3.61 billion rand across the company and climbed more than 100 percent in its international business.

Vodacom, 65 percent owned by Newbury, England-based Vodafone, is expanding in newer, high-growth territories such as Mozambique and the Democratic Republic of Congo.

Its goal is to offset falling domestic voice revenue, which is under pressure following proposed cuts in the rates it’s allowed to charge for terminating calls on its network.

“This quarter highlights once again that our strategy of sustained network investment is key to allow us to grow our overall business while still driving down the cost to communicate,” chief executive Shameel Joosub said in the statement.

Joosub said in December that the company will spend more than 9 billion rand this year on infrastructure in South Africa as it adds high-speed, fibre Web service to homes and businesses.

Vodacom said in September that it’s in exclusive talks to acquire Internet provider Neotel.

The number of active customers rose about 12 percent to 56 million in the quarter compared with a year earlier, the company said.

South African customers increased 5.1 percent to 31 million, while Mozambique was its fastest growing market, expanding 44 percent to 4.1 million subscribers.

Vodacom shares gained 3.5 percent to 119.75 rand by the market close in Johannesburg yesterday, its biggest daily gain since November 15.

The stock has fallen 10 percent this year, compared with an 8.8 percent decline at Johannesburg-based competitor MTN. - Bloomberg News