South Africa’s mobile market is undergoing a structural shift as challenger operators start to capture high-value subscribers from market leaders.

According to Opensignal’s latest subscriber analytics data, the shift is no longer price-led, but driven by quality.

South Africa’s largest mobile operator, Vodacom, has lost seven percentage points of market share, from 43% in the first quarter of 2024 to 36% in the fourth quarter of 2025.

While MTN absorbed some of that user base, increasing two percentage points from 29% to 31% in the same period, most of the subscriber gains are concentrated among challenger operators Telkom and Cell C.

Telkom recorded a three- percentage-point increase from 16% to 19%, while Cell C’s market share increased one percentage point from 8% to 9% during the same period.

“This is no longer just prepaid churn at the margins. Incumbents are now exposed in higher-value segments. This disruption is not price-led, but rather quality [driven],” Opensignal says, noting that the challengers’ growth is being driven by improved network quality and targeted commercial execution.

Both Telkom and Cell C relied heavily on aggressive prepaid pricing to acquire price-sensitive users, a strategy reflected in their traditionally lower average revenue per user.

“Today, however, that model is evolving. Powered by a rapid quality catch-up, these challengers are increasingly capturing higher-margin, top-tier subscribers who are migrating away from legacy networks.”

As consistent quality improves, they are increasingly attracting higher-value subscribers who were previously locked into incumbent networks.

This also emerges as capital is reallocated from network resilience to network optimisation and improving performance amid stabilisation in South Africa’s electricity grid.

Opensignal explains that persistent load-shedding forced the industry to spend heavily to ensure towers were powered at all times, with the Independent Communications Authority indicating that operators spent about R2.6-billion on backup batteries in 2023/24 alone.

“For the past five years, competition was defined by survival – who had the capital to keep the towers powered during outages? That chapter is closing. It signals that the market has crossed a threshold into the post- resilience era.”

This has led to baseline network reliability for the entire country increasing.

The transition to optimisation is accelerating improvements in network quality, particularly among challenger brands, which are bringing their network experience progressively closer to that of market leaders and reducing the historical gap with incumbents.

This removes a key barrier to switching: high-value users no longer need to trade reliability for price, making them more willing to consider alternative providers.

Meanwhile, according to Opensignal’s subscriber analytics, win/loss composition data shows Vodacom is steadily losing share, mainly to MTN, a migration that aligns with local network performance and MTN’s advantage in consistent quality across markets.

“National averages, however, mask important regional dynamics. In major economic centres like Cape Town and the City of Tshwane, MTN outperforms its competitors in consistent quality. Yet here in these specific metropolitans, MTN currently holds an underweight market share relative to its national average,” Opensignal notes, pointing out that the localised superiority is not an accident.

MTN’s aggressive R1.5-billion investment strategy to counter load-shedding and upgrade base-station power resilience is now acting as a primary commercial lever.

“By delivering a measurably higher consistent quality in these specific regional pockets, MTN is effectively attracting premium, data-centric subscribers, particularly those using high-end devices that unlock superior 5G mobile experiences, who value reliability above all else.

“Telkom and Cell C present a highly effective value-quality intersection strategy. While they may still sit slightly lower on the overall consistent quality matrix compared to MTN, their networks have crossed the threshold of good enough for the modern high-value consumers.”

Opensignal’s previous analysis shows that between May 2023 and the end of 2024, Cell C’s consistent quality increased by 15 percentage points, while Telkom saw steady, sustained gains to push its network parity forward – momentum that is continuing, according to more recent consistent quality data.

By transitioning to a virtual RAN model operating on MTN’s infrastructure, Cell C instantly elevated its network.

“Rather than fighting a capital expenditure (capex) war, they are using this improved, outsourced consistent quality to offer exceptional digital experiences and aggressive data value.”

Cell C is also leveraging this reliable baseline to host mobile virtual network operator partners, such as Capitec.

Telkom is driving active user growth through lower prices, as well as aggressive network and regional expansion.

“For example, a regional expansion strategy targeting under- indexed, non-metropolitan areas has gained massive traction, with Telkom reporting a 5.6% increase in its share of subscriber acquisitions in those regions,” Opensignal explains.

“Paired with tailored data platforms such as Mo’Nice and Mo’Town and R5.8-billion in capex that delivered a core network availability of 99.99% and a net promoter score of 72.3, Telkom is offering a friction-free experience that attracts switchers across all demographics.”

By achieving this baseline of reliable consistent quality, challengers opened the door to acquiring high-value users who would not have previously considered switching from the market leader.

“This multiyear quality catch-up laid the foundation for the subscriber migration we are witnessing in the market today.”