A price analysis produced by the Independent Communications Authority of South Africa has found that start-up mobile operator, Rain, offered the cheapest rate for a prepaid 1GB data bundle at R50.
The report analysed data for the period July 1, 2016 - December 31, 2018.
The "One Plan Package" offered by the Stellenbosch-based newcomer beat larger competitors, Vodacom, MTN, Cell C and others.
The bi-annual report showed that MTN and Vodacom each charged R148 for a 1GB bundle, while a 3GB data bundle with the same networks set customers back R299.
The high cost of data has been a source of major debate in the country and prompted the #datamustfall movement, which is lobbying for lower rates.
The regulator said the report is aimed at ensuring "retail price transparency within the electronic communications sector... to enable consumers to make informed choice[s]" in terms of tariff plan preferences.
"It is worth nothing that Rain offers non-expiring data, meaning it has no validity period and its out of bundle rate is the lowest in the market at R0.05 per megabyte."
Afrihost's month to-month mobile prepaid data plan offered a 1GB bundle at R68, making it the second-most affordable bundle, followed by Telkom Mobile at R100.
In terms of calls, the report analysed flat-rate tariffs as well as on-net tariffs, where subscribers are given discounts for calling cellphone users on the same network.
It also looked at dynamic tariffs, offering rates based on the time of day and location.
The table below shows per-second tariff plans by different service providers. Cell C had the lowest per-second tariff plan, at 66c per minute, followed by Vodacom at 79c per minute.
MTN charged 99c per minute on its pay-per-second plan, the highest rate compared to the other licensees.
Vodacom had a flat rate of R1.23 per minute for both on-net calls and calls to another network for the period under review. MTN charged a flat rate of R1.20 for both on-net and off-net voice calls per minute.
The report stated that MTN charges a flat rate of R1.20 for both on-net and off-net voice calls per minute, meaning its customers pay 2.4% less than Vodacom customers when making on-net calls.
ICASA said it had observed competitiveness between licensees in terms of promotions, with 31 such offerings launched during the period under review.