marketing SMS that gets read names the sender in the first words, leads with one specific offer, fits in a single segment (160 GSM-7 characters or 70 Unicode characters), ends with one call to action, and tells the reader how to opt out, for example "Reply STOP to opt out". Send it only to people who opted in, at a sensible local time, and measure the result. The rest of this guide is the detail behind each of those lines.
Key takeaways
- Structure: brand, offer, detail (deadline or code), call to action, opt-out.
- Length: one segment is 160 GSM-7 or 70 Unicode characters; one emoji can switch the whole message to Unicode.
- One message, one action: a single link or reply keyword.
- Compliance: consent, sender identification and a free opt-out in marketing messages.
- Test and measure: compare versions on click-through, conversions and opt-outs.
What is the best structure for a marketing SMS?
| Part | Purpose | Example |
|---|---|---|
| Brand | Tells the reader who is writing, even if the sender ID is short | Nova Café: |
| Offer | The reason to read on, specific and concrete | 20% off all breakfasts |
| Detail | Deadline, code or condition | until Sunday with code SUN20 |
| Call to action | One thing to do | Order: nova.cafe/o |
| Opt-out | Required for marketing in most markets | Reply STOP to opt out |
Put together: "Nova Café: 20% off all breakfasts until Sunday with code SUN20. Order: nova.cafe/o Reply STOP to opt out". That is under 110 characters, one segment, one action.
How long should a marketing SMS be?
Aim for one segment. With the standard GSM-7 character set a single SMS holds 160 characters; if any character is outside it, such as an emoji, curly quotes or many accented letters, the message switches to Unicode (UCS-2) and a single SMS holds 70. Longer messages are split into parts of 153 or 67 characters, and each part is billed. Arabic, Hindi, Chinese and other non-Latin scripts always use Unicode, so plan for 70 characters per segment. See the SMS character limit and GSM-7 and UCS-2 encoding.
How do you write a strong call to action?
- Use one action per message: a link, a reply keyword or a code, not all three.
- Put the verb first: "Book", "Order", "Claim", "Reply YES".
- Use a short, branded link so readers can see where it goes; unbranded shorteners look like phishing. See branded short links for SMS.
- Say what happens next: "Reply YES to confirm your slot".
What must every marketing SMS include to stay compliant?
Rules differ by country, but most markets require three things for marketing messages: prior consent (or a narrow existing-customer exception), identification of the sender, and a free, working opt-out. Some add sender-ID registration, content categories or permitted sending hours. Examples from our country guides:
- UK: PECR consent or the soft opt-in, sender identification and a free opt-out; see UK SMS marketing rules.
- South Africa: POPIA section 69 consent, sender identity and opt-out in every message; see South Africa SMS marketing and POPIA.
- Kenya: opt-in consent and promotional sends only between 07:00 and 19:00; see bulk SMS in Kenya.
Use the SMS compliance checklist and the country pages under SMS regulations before each new market.
What should you avoid in an SMS?
- Shouting: all capitals and strings of exclamation marks read as spam and can trigger filters.
- Vague offers: "Big sale now!" gives no reason to act; a number or a deadline does.
- Link-only messages and unbranded shorteners, which look like smishing.
- Personal or sensitive data in the text: account numbers, health details, full names of third parties.
- Promotions inside service messages: it turns a transactional message into marketing.
- Sending at night: respect local time and any legal send windows.
Before and after: three rewrites
| Before | After | Why it is better |
|---|---|---|
| BIG SALE!!! Visit our website now for amazing deals!!! | Luma Home: 30% off sofas until 5 Oct. Shop: luma.home/s Reply STOP to opt out | Brand, specific offer, deadline, one link, opt-out |
| Dear customer, we would like to remind you that your appointment is scheduled for tomorrow. Please let us know if you cannot come. | City Clinic: your appointment is tomorrow at 10:30. Reply YES to confirm or R to reschedule. | Shorter, time first, two clear reply options |
| Don't miss out 😍 new arrivals just landed, check them out | Kora Shoes: new autumn boots are in. First 100 orders get free delivery: kora.shoes/b Reply STOP to opt out | No emoji (stays GSM-7), specific reason to act |
How do you personalise and test SMS copy?
Personalise with data the reader expects you to have: first name, the store they visit, the product they bought. Keep a fallback for empty fields so nobody gets "Hi ,". Test one variable at a time (offer, wording or send time) on a slice of the list, then send the winner. Measure clicks, conversions and opt-outs per version; our guide to SMS campaign metrics explains which numbers to watch, and the best time to send bulk SMS covers timing.
BroadNet's bulk SMS platform and SMS marketing tools support templates, personalisation fields, scheduling and branded links.
Frequently asked questions
How many characters should a marketing SMS have?
Keep it within one segment: 160 characters in GSM-7, or 70 if the message uses Unicode, for example because of an emoji or a non-Latin script.
Should I use emojis in SMS marketing?
Sparingly, if at all. One emoji switches the whole message to Unicode, cutting a segment from 160 to 70 characters and often doubling the cost.
Do I need to include an opt-out in every marketing SMS?
In most markets, yes. A short line such as "Reply STOP to opt out" is the common form.
Where should the brand name go?
In the sender ID and, if the sender ID is short or numeric, in the first words of the message.
How many links should an SMS contain?
One, on a branded domain, so readers can trust where it goes.
How do I know if my SMS copy works?
Test versions on a slice of your list and compare click-through, conversion and opt-out rates.
Brand names in the examples are fictional. Reviewed 28 September 2026. See our editorial standards.