Open rates are not the problem with SMS — almost everyone reads it. The problems are consent, content rules that carry real penalties, and measuring anything beyond "sent".
Under Malaysia's Personal Data Protection Act, a phone number collected for one purpose cannot be reused for another. A number given at checkout so the courier can call is not automatically a marketing list. Practically, that means three things:
Detail in our PDPA compliance guide. Beyond the law, consent is also the single strongest predictor of delivery: lists that never opted in generate complaints, and complaints are what get a sender filtered by the operators.
Malaysian operators penalise messages containing protected international brand names at RM1.50 per segment, per recipient. Marketing copy is exactly where these appear — "now on [marketplace]", "pay with [wallet]", "faster than [courier]".
A single-segment promo to 1,000 recipients mentioning one protected brand is a RM1,500 penalty on roughly RM200 of traffic. Describe the channel generically ("available online", "cash on delivery") unless you have written permission to use the brand.
A marketing SMS has to identify you, state the offer, tell the reader what to do, and give an opt-out — inside one segment if you want the economics to work.
[BrandName] 20% off all repairs this week. Book: yoursite.com/bk To opt out, WhatsApp 012-345 6789.
What that example is doing: brand first, because an unidentified sender reads as a scam. Offer in one clause. One link, on your own domain — public URL shorteners share reputation with whatever else was sent through them that week. Opt-out present, in the same message — pointing to your own WhatsApp or phone number, because recipients cannot reply to our shared short code 66886.
Watch the encoding. One emoji or one curly apostrophe pasted from Word converts the message to Unicode and drops the segment limit from 156 characters to 66 on our route — tripling the cost of the campaign without changing a word. Check with the segment calculator before you send.
Business hours only — before 9am or after 9pm generates complaints out of proportion to any benefit. Lead time beats precision: a few hours before an offer opens consistently outperforms sending the moment it does. On frequency, the honest guidance is that SMS tolerates far less than email. More than two or three promotional messages a month to the same list and opt-outs climb faster than revenue.
"Sent" is not a result. Three numbers are worth tracking:
Cost per outcome is then arithmetic you can actually do: segments × recipients × rate, divided by conversions. Because there is no monthly platform fee, a small campaign is not carrying overhead from a subscription you are only half using.
SMS is worth its cost when the message is short, time-sensitive and needs to be seen without an app. It is a poor fit for long-form content, image-heavy promotion, or anything where a reply conversation is the point. That comparison in full: SMS vs WhatsApp for business in Malaysia.
Yes, with consent. The Personal Data Protection Act requires that personal data is used only for the purpose it was collected for, so a number collected for delivery is not automatically a marketing list. You need consent recorded at collection and a working opt-out that persists across campaigns.
You must provide a working way to opt out, and including it in the message is the practical way to do that. We send from the shared short code 66886, which recipients cannot reply to — so a Reply STOP line will not work. Put your own WhatsApp or phone number in the message so recipients can ask to be removed, and delete them from your own list.
Less than you would send email. Two to three promotional messages a month to the same list is a reasonable ceiling for most businesses. SMS is interruptive by nature, and opt-out rates climb faster than revenue past that point.
Almost always encoding. One emoji, one Chinese character or a curly apostrophe pasted from a word processor converts the whole message to Unicode, cutting the per-segment limit from 160 characters to 70. The other cause is the 4-character prefix our upstream route adds to every message, so one segment actually holds 156 plain-English characters, or 66 in Unicode.
Not safely. Malaysian operators maintain a list of protected international brand names and penalise messages containing them at RM1.50 per segment per recipient — which on a large list exceeds the value of the campaign several times over. Describe the service generically instead.
RM1 trial credit (claim it on WhatsApp after signing up), no monthly fee, and per-number delivery reports so you can see what actually landed.