Every year someone writes an article declaring SMS dead. And every year your bank sends you an OTP, your kid's school moves practice to 4pm by SMS, your municipality warns you about a water outage by SMS, and the courier tells you the driver is outside by SMS. The channel that has been dying since 2010 is, somehow, still the one thing every serious organisation in the country reaches for when a message absolutely has to arrive.
We've been in South African prepaid since 2003, and we've watched businesses send millions of these messages. Some of them build customer relationships that last decades. Some of them get their sender blocked, reported, and quietly hated. The difference is never the technology. It's the thinking. So this is the guide we'd hand to a friend starting out: what SMS is genuinely good at, where the law draws its lines, and how to write a message that gets read instead of resented.
Why a 30-year-old technology still wins
Two reasons, and they're both unglamorous.
The first is reach. An SMS arrives on a R6,000 iPhone and a R150 feature phone with equal certainty. It needs no app, no data, no smartphone, no updated OS. In a country where data is expensive and a significant share of your customers are not on the latest handset, that is not a small thing. It is the whole thing. WhatsApp is wonderful, but WhatsApp requires WhatsApp. SMS requires a SIM card.
The second is the empty inbox. Your marketing email lands in a folder with two hundred competitors, most of which will never be opened. The SMS inbox contains OTPs, the bank, and someone's mother. Almost nothing else. When your message lands there, it gets read, usually within minutes, because there is nothing else to read.
That second point is also the warning. The SMS inbox is quiet because people guard it, and networks and regulators guard it with them. The privilege of landing somewhere people actually look comes with the responsibility of deserving to be there. Which brings us to the biggest mistake in the industry.
The mistake: thinking "bulk SMS" means "advertising blast"
Ask most people what bulk SMS is for and they picture a Saturday-morning promo: "MEGA SALE!!! 50% OFF!!!" fired at ten thousand numbers of uncertain origin. That message is why the channel has a bad name. It is also, commercially, the weakest thing you can do with it.
The businesses that get real value from SMS mostly aren't advertising at all. They're operating:
A workshop tells you your car is ready. A doctor's rooms remind you about tomorrow's 9am appointment, and their no-show rate drops by a third. A school tells four hundred parents the athletics day is moved before four hundred parents drive there. A debtors' clerk sends "Payment received, thank you" and the phone stops ringing with people asking if their EFT went through. A landlord's system warns a tenant their prepaid electricity is nearly finished, at 6pm, before the geyser dies at 9.
Notice what those have in common. Nobody opts out of them. Nobody resents them. Each one replaces either a phone call someone had to make or a problem someone had to have. That is the actual product: not attention, but coordination. If you take one idea from this whole article, take this one. Start with the messages your customers would thank you for, and earn the right to send anything else.
Promotional SMS can work too, to be clear. A salon filling two empty Saturday slots, a butchery telling regulars the lamb special is on. But it works when it goes to people who know you, want to hear it, and were asked. Which is not just good manners. In South Africa, it's the law.
The law, without the lawyer
POPIA scares people off SMS unnecessarily, mostly because nobody explains the first and most important distinction: the strict rules apply to direct marketing, not to messages people asked for.
"Your order has shipped" is not direct marketing. Neither is an appointment reminder, a payment confirmation, a delivery notice or an OTP. Those are part of the service the person signed up for, and section 69 of POPIA is not aimed at them. If everything you send is operational, your compliance burden is mostly just handling personal information properly, which you had to do anyway.
The moment a message tries to sell something, section 69 wakes up, and it splits the world into two groups:
People who are already your customers. You may market to them by SMS without fresh consent, provided three things are all true: you got their number in the course of a sale, you're marketing your own similar products or services, and you gave them a chance to opt out when you collected the number and you give them one in every message. Miss any leg and the exception falls away.
Everyone else. Strangers are opt-in. You get exactly one message to ask for their consent, in the format the Information Regulator prescribes, and if the answer is no or nothing, that's the end of it. Buying a list of "opted-in" numbers from a broker and blasting it does not launder anyone's consent, whatever the invoice says.
And in every marketing message, two things: say who you are, and give a way out. "Reply STOP to opt out" costs you 21 characters and keeps you on the right side of both the Regulator and human decency. When someone does opt out, it goes into a register and they never hear from you again. Not "after this last campaign". Ever.
None of this is legal advice, and edge cases exist, so run your specific setup past someone qualified. But the practical summary has held up for years: be useful by default, sell only to people who said yes, always sign your name, always offer the door.
Writing a message people actually read
You get 160 characters. Treat that as a discipline, not a limitation, because the constraint is doing you a favour: it forces you to know what you're actually trying to say.
First, the trap that catches almost everyone. The 160-character limit only holds if you stick to the basic character set. Add a single emoji, or even a curly quote pasted from Word, and the encoding silently switches, your limit drops to 70 characters, and your one message is billed as two or three. That 🎉 in your promo just doubled or tripled the cost of the entire campaign. Plain text, straight quotes, no emoji. Your accountant will thank you.
Second, answer "who is this?" in the first three words. A message from an unknown number that starts with "Hi! Great news!" is deleted before the thumb finishes scrolling. Your business name goes first, always. Not because a regulation says so (though for marketing, one does), but because an unsigned message is a message from nobody.
Third, one message, one job. Here's the kind of thing that goes out every day in this country:
Dear Valued Customer, We are excited to announce our AMAZING SUMMER SALE with discounts of up to 50% on selected items in-store!!! Don't miss out, visit us today! T&Cs apply.
Nobody has a valued customer. It's over the character limit, it names no sender, offers no way out, and asks the reader to do nothing in particular. Now the same intent, done properly:
Zinhle's Salon: 2 open slots this Saturday. Book on 071 234 5678. Reply STOP to opt out.
Eighty-eight characters. The reader knows who, what, and what to do about it, in the time it takes to glance at a lock screen. That's the entire craft. Front-load the sender, state the one thing, give the one action, sign off with the exit.
Last, send it to yourself before you send it to five thousand people. Every seasoned SMS sender has a story about the typo, the wrong date, or the test message that went to the full list. The people with only one such story are the ones who started sending themselves the message first.
Your list is the asset. Treat it like one.
The message is what people see; the list is what decides whether the campaign works at all. Three things about South African number lists that nobody tells beginners:
Numbers die quietly. Networks recycle prepaid numbers that go inactive, which means the loyal customer from a few years back may now be a stranger, and a message "to your customers" is landing on people who've never heard of you. Old lists don't just waste money on dead numbers; they leak messages to the wrong humans.
Numbers move. Porting means the prefix tells you nothing reliable about the network anymore, which matters for anything network-specific and for keeping your records honest. Before a big send, a network lookup across the list is cheap insurance.
And your opt-out register is part of the list, not a separate afterthought. The fastest way to poison years of goodwill is a "whoops, the old spreadsheet" send to people who asked to leave.
Keep one living list, prune it, honour it, and it compounds in value every year. Keep six overlapping spreadsheets and every campaign is a small gamble.
The mechanics, and the money
The workflow itself is the easy part, and it hasn't fundamentally changed in fifteen years: one spreadsheet, one column of numbers, one message, one upload, and a delivery report afterwards. Our step-by-step bulk SMS guide walks through it on SIMcloud, and if you ever want your own software doing the sending, the same account drives the SMS API.
On cost: bulk SMS in South Africa is priced per message, typically somewhere in the twenty-to-forty-cent range depending on volume and provider, with no reason to accept monthly platform fees on top. The arithmetic is friendlier than it looks. A thousand messages costs about what one newspaper ad used to, and a single prevented no-show, one filled appointment slot, or one avoided "did my payment go through" phone call pays for a hundred of them. SMS fails commercially almost only when the message wasn't worth sending, which no price could have fixed.
One honest note on delivery reports, because providers love waving them around: "delivered" means the handset accepted the message. It does not mean read, and it cannot mean read by the right person. Reports are excellent for spotting dead numbers and network problems. They are not proof of attention. The only proof of attention is what your messages have earned over time, which is the point this whole article has been circling.
The businesses that win with SMS aren't the ones with the biggest lists or the loudest promos. They're the ones whose name on a lock screen makes a customer think "this will be worth reading". That reputation is built one useful message at a time, and it is, genuinely, the entire game.
If you want to start on the useful end of it, a free SIMcloud account takes a few minutes, there are no monthly fees, and your first send can be to a list of one: yourself.