A lag in data means South Africa’s inflation rate – 3.1% year-on-year in March as of yesterday’s Stats SA print – may not reflect lived realities, a dynamic that the use of fintech-based transaction data could resolve.
This is according to Jed da Silva, co-founder and head of product at start-up Maholla, which has created a consumer rewards and market research app. He says shifts in consumer behaviour are happening weekly and is a behavioural trend that transaction devices pick up and is more accurate than the lagged inflation print.
“By the time Consumer Price Index (CPI) data is published, households have already made their adjustments: switching brands, splitting purchases across cheaper stores, quietly removing items from the basket altogether. The statistic confirms what families have already lived through.”
As a result, Da Silva says even though official metrics suggest relief, “consumer behaviour reveals a population under sustained pressure, quietly removing items from baskets and abandoning brand loyalty to survive”.
Under pressure
Year-on-year, the cost of living officially gained a percentage point from February’s 3%, driven by housing and utilities, which was up 5.1%; food and non-alcoholic beverages, which gained 3.6%; and insurance and financial services, up 5.6%.
Education was also a key driver as primary and secondary education rose 6.2% year-on-year, tertiary education gained 4.2%, while private secondary schools recorded the sharpest rise in 2026 at 7.5%.
Da Silva argues that retail-agnostic data systems, used across formal and informal retail segments, could detect financial stress as it emerges rather than months after the fact.
Patrick Kelly, chief director of price statistics at Stats SA, points out that the CPI being published with a one-month lag is the international standard. “It is designed to reflect changes in prices of consumer goods and services over the whole month.”
South African Reserve Bank figures published at the end of March showed that consumer debt increased further in the fourth quarter of 2025, with household debt as a percentage of disposable income equated to 61.8c for every R1, up from 61.5c in the third quarter of last year.
Recently released research from the Competition Commission shows that while headline inflation has eased, the cost of essential goods and services rose at a faster pace between 2020 and the end of 2025. Inflation at the end of 2025 was at a 21-year low of 3.2%.
Lagged fuel shock
Most economists see the inflation print ticking up, warning that the effects of the April fuel hike as well as any inflationary pressures on food will only be reflected in the next set of data.
Annabel Bishop, Investec chief economist, says the oil price shock, which led to petrol increasing R3.06 and diesel moving up as much as R7.51 on 1 April, will only come through in April’s CPI data. “For the year as a whole, inflation is forecast around 3.8% year-on-year… but the risk remains to the upside.”
Standard Bank Group head of South Africa macro-economic research Dr Elna Moolman concurs. “The data doesn’t yet reflect the full inflationary impact after the Iran war, which will have a more significant impact on April’s inflation rate given the spike in fuel prices at the beginning of April.”
PSG senior economist Johann Els predicts April’s CPI will come in at around 3.7% or 3.8%, depending on whether government extends the fuel levy relief it granted in May, when it absorbed R3 a litre for petrol and diesel. Els is optimistic there will be only one rate hike this year of 25 basis points, likely in the second half of the year.
April’s data will be published on 20 May, in time for the South African Reserve Bank’s Monetary Policy Committee meeting scheduled for 28 May. Markets expect either a 25-basis point increase at that meeting or the following one in July.
Limited basket
Da Silva also points out that StatsSA’s basket excludes a significant portion of where South Africans actually spend.
Just over two-fifths of FMCG purchases move through the informal sector, spaza shops, township traders and neighbourhood convenience stores, which he says are “almost entirely invisible to the datasets used to guide policy and business decisions”.
Kelly, however, disagrees: “The CPI basket does not distinguish the channel through which goods and services are sold. CPI data collection does cover food sales in the informal sector.”
Not all items in its basket are surveyed monthly – rentals are only included on a quarterly basis, while education is only captured in March. In 2025, the agency said it had “shaken up the basket of goods and services used to measure consumer inflation. The products in the basket are updated periodically to better reflect shifts and trends in consumer spending.”
South African consumers completed over 118 card transactions per person in 2025, with total card volume reaching R2.9 trillion, Da Silva says. The data infrastructure exists, he notes, what’s missing is using it as a real-time economic measure rather than just a commercial tool.
Kelly, however, says transaction data on payments typically reflect the amounts paid by consumers and not the breakdown of the specific products and the prices attached to these.
Real-time signals
“While there is a growing body of work on ‘nowcasting’ we do not currently view this as part of the portfolio of official statistics,” says Kelly.
Research published in the International Journal of Current Research shows that transaction data can improve how quickly economic activity feeds through into policy decisions. India, the researchers note, is already using digital payments to strengthen how changes to monetary policy feed through the economy.
In Zambia, a paper published in the African Journal of Empirical Research found that current price monitoring tools, including the CPI, are constrained by monthly reporting intervals that mask intra-period price fluctuations, meaning rapid price changes went unnoticed in real-time and limited the ability of policymakers and families to respond to affordability crises.
The MIT Billion Prices project, launched in 2007, collected millions of online prices daily to measure inflation in near-real-time, demonstrating that high-frequency digital price data can closely track, and often anticipate, official CPI trends published monthly with a lag.
“The data is already there – in every receipt, every basket, every purchase quietly removed from a shopping list,” says Da Silva. “We just need to start listening to it in real-time.”
“Stats SA is exploring is the use of supermarket point-of sale-data,” says Kelly. “We have received positive feedback from retailers in relation to this. Sadly, due to the financial constraints that we are under, we do not have staff that we can dedicate to this work and so progress is slow.”
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