Cell C has been struggling to take market share from rival operators Vodacom and MTN Group in South Africa, and requested the extension from bondholders in July 2014.
The debt has now been pushed back to 2018, and the company has established a new pricing strategy in a bid to win customers.
The operator reportedly plans to invest $215 million in upgrading its network infrastructure over the next year.
Earlier in January, regulators in South Africa announced that they were halving the fees mobile operators can charge rival players to use their network.
