South Africa sells mobile data at some of the lowest prices in Africa and asks more questions than most places before it hands it over. Both halves of that sentence matter to a visitor.
The five networks
Vodacom is the largest and, along with MTN, has the widest national coverage. Between them they reach the small towns, the main tourist routes and much of the countryside, which is why a self-drive trip usually comes down to a choice between those two.
Cell C and Telkom are the smaller players. They compete on price and they roam on the larger networks, so in a city the experience is close to identical and the cost is lower. Outside the cities the difference starts to show.
Rain is different in kind: it sells data only, with no voice line, and it has grown by offering unlimited data products. For a visitor who wants data and does not need a South African phone number, it is a reasonable fit and an unusual one.
For where each of them actually reaches, what the coverage looks like goes through it properly.
The registration rule
South Africa requires every SIM card to be registered to a named person before it can be used. This comes from a law known as RICA, which has been in force since the late 2000s, and it applies to prepaid cards as firmly as to monthly contracts.
For a South African that means a national identity document. For a visitor it means a passport, presented in person at the point of sale and recorded by the shop. You cannot buy a working prepaid SIM in South Africa without it, and no shop will bend the rule, because the penalty falls on them rather than on you.
The practical effect is that buying a SIM is a small errand rather than a vending machine transaction. It takes minutes once you are at the counter, and the counter is where the time goes.
What it costs
Data is cheap. The networks compete on how much they give you for a monthly bundle rather than on the price of the card, and a visitor buying a week’s worth is spending a small amount by European standards.
Topping up is easy and worth knowing about, because the system is geared around vouchers. Airtime and data vouchers are sold in supermarkets, petrol stations, convenience stores and small shops, so running out is not a problem you solve by finding a network shop.
Two choices make a real difference to the bill. Buying a bundle is much cheaper per gigabyte than using prepaid airtime at the standard rate, so it is worth asking for a data bundle rather than simply loading airtime. And an out of bundle rate is punishing, so knowing when your bundle expires prevents the expensive surprise.
Where to buy
The airport is the obvious place and, as in most countries, not the right one. Johannesburg and Cape Town both have network presence in arrivals, and the staff register visitors constantly, but the counters are slower and dearer than a shop in town and they close when the airport goes quiet.
A network shop in a mall is the better option if you are arriving during the day. Staff are quick, the range of bundles is the full range rather than a tourist subset, and if something is wrong with the card you can walk back in.
If you are driving from the airport, one practical sequence works well: collect the car, drive to your accommodation, and buy the SIM at a mall that evening. Trying to do all three at the airport is where the first day goes.
The comparison worth making
A local SIM gives you a South African number, which is genuinely useful if you want a guesthouse to reach you, or you want to call a restaurant or a tour operator. It also gives you data at local prices rather than at roaming ones.
A travel eSIM gives you data without the errand. No passport, no counter, no registration, and it works from the moment you switch it on. Data only, so calls go through apps, which in South Africa is barely a limitation, because WhatsApp is close to universal.
For a city trip or a route you have booked in advance, an eSIM for South Africa is the simpler answer. For a long stay or a trip where you will be making local calls, the SIM earns the extra twenty minutes.
One last note on the money. Prepaid in South Africa is priced in rand and topped up in rand, so the exchange rate moves your cost in euros without changing the local price. What the rand does covers how the currency works, including why cards are the normal way to pay for everything else.