MTN South Africa has lost roughly 1.5 million consumer prepaid customers since the start of the year, and says it did so deliberately. The prepaid base fell from 29.7 million in December to 28.2 million at end-June, down 4.5% year on year, pulling the total base down 0.7% to 39.5 million after growing 3% as recently as the first quarter.

The cull targets customers who depend on borrowed airtime.

The strategy is defensible on MTN's own numbers. It has been cutting back XtraTime, which lends prepaid users airtime and data, and steering them towards cash recharges.

In-month repayment rates have moved from about 50% in October 2025 to 70% now, leaving materially lower outstanding balances. Cash recharges grew 9.4% excluding advance repayments, prepaid data revenue rose 4.4%, and consumption jumped 23.6% to 4.9GB per subscriber. The bill lands elsewhere. Fintech revenue, which includes XtraTime, fell 16.3% to R701-million, and digital services dropped 7.5%.

Voice is the harder problem. Revenue fell 10.2% across the half against 9.6% in the first quarter, making four consecutive quarters of decline with the rate rising each time. EBITDA fell 7.6% to R8.5-billion and the margin hit 34.2%, below the 35% to 37% band MTN reaffirmed. South Africa now delivers 19% of group service revenue but only 15.2% of group EBITDA.

TechCentral reported the results and the arithmetic behind the voice decline: Capitec Connect scrapped charges on calls between its own SIMs in April and carried 768 million voice minutes in the year to February, up 150%, selling a banking relationship rather than minutes. Business Day covered the profit warning two weeks ago, in which MTN described the prepaid pressure as previously communicated and expected. TechCentral's earlier analysis noted MTN has now anticipated this decline four times running without arresting it.

Two lessons here, and only one is comfortable. Culling customers who cost more than they pay is genuine discipline, and most South African businesses would benefit from running the same audit. MTN traded 1.5 million subscribers for a repayment rate that went from 50% to 70%, and that is a better business even though the headline reads worse.

The uncomfortable lesson is voice. Capitec is not undercutting MTN on minutes, it is giving them away because the money sits in the banking relationship underneath. You cannot price-match free. If your revenue rests on a line item somebody else can treat as a loss leader, the pricing lever is already gone, and the only move left is changing what you sell.

You might also like our piece on how Cell C launched 5G without building it, why Capitec home broadband is the next front in the same fight, and how WhatsApp web calling keeps draining operator voice revenue.

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