Transactional SMS carries information the recipient needs about an action or account (OTPs, order updates, alerts), while promotional SMS advertises products or offers. Promotional messages usually need prior consent, an opt-out, sending-hour limits and sometimes a separate sender ID or route; transactional messages have fewer limits but must not contain marketing.
The difference in practice
| Transactional | Promotional | |
|---|---|---|
| Purpose | Inform about an action, account or service | Sell, advertise, re-engage |
| Examples | OTP, delivery update, payment alert, appointment reminder | Discount, new product, event invitation |
| Consent | Usually covered by the customer relationship | Usually explicit opt-in required |
| Opt-out text | Often not required | Usually required (for example "Reply STOP") |
| Sending hours | Any time | Often restricted to daytime in many countries |
| Do-not-disturb lists | Usually exempt | Must be respected where they exist |
OTP is often treated as its own category, with stricter templates and priority routing. See OTP SMS best practices.
Where the line is drawn
The test is the content, not the sender's intention. A delivery notification that ends with "Use code SAVE10 on your next order" is promotional in most regimes, because it contains marketing. Mixing the two is one of the most common reasons messages get blocked or templates get rejected. Keep them separate: different templates, often different sender IDs, and in some countries different routes.
Why the classification affects routing
- Separate routes: many suppliers sell OTP, transactional and promotional routes separately. A transactional route used for marketing can be suspended.
- Separate registration: in India, sender IDs (headers) and templates are registered by category on the DLT platform, and promotional traffic uses numeric headers. See India DLT registration.
- Consent registries: in Turkey, commercial electronic messages are subject to the IYS consent system. See Turkey sender ID and IYS rules.
- DND lists: some countries let subscribers block promotional SMS, as covered in Nigeria sender ID rules and DND.
- US campaigns: 10DLC campaigns are registered with a declared use case such as 2FA, account notifications or marketing, and the content must match it.
- Price: in some markets promotional and transactional traffic are priced differently. See how A2P SMS pricing works.
Rules for promotional SMS
Details vary by country, but these apply almost everywhere:
- Get clear consent before sending, and keep a record of when and how it was given.
- Identify the sender in the message.
- Include a simple opt-out and process it quickly.
- Respect local sending hours and holidays.
- Avoid restricted categories (gambling, loans, alcohol, and others depending on the market). See SMS content restrictions by traffic type.
Rules for transactional SMS
- Keep content strictly informational and tied to an action the user took or an account they hold.
- Use templates where the country requires them, and keep variable parts short.
- Send only to the person concerned, never to bought lists.
- Use a fast route: a delivery notice or OTP that arrives late loses its value.
Requesting the right route
When you request A2P SMS routes through VoIPMatcher, state the traffic type for each country. We source routes from our carriers that accept that traffic, so it is not blocked later. Request a transactional or promotional SMS route.
Frequently asked questions
What is transactional SMS?
Transactional SMS is a message the recipient needs because of an action they took or an account they hold: one-time passwords, order and delivery updates, payment alerts, appointment reminders and receipts. It must be purely informational. As soon as it contains an offer or discount code, most regimes treat it as promotional.
Can I send promotional SMS to DND numbers?
Not in countries with a do-not-disturb or consent register. Numbers on India's NCPR or Nigeria's 2442 DND service, for example, do not receive promotional messages, and sending to them can get your sender suspended. Transactional messages are usually exempt, provided their content is strictly informational and they go on a transactional route.
Is OTP transactional or promotional SMS?
OTP is transactional, and many providers and countries treat it as its own category with stricter templates and priority routing. In India, bank OTPs go under the transactional category and other OTPs under service. Keep OTP messages free of any marketing line, or they can be reclassified as promotional and blocked.
Is transactional SMS priced differently from promotional SMS?
In some markets, yes. Operators and suppliers may price OTP, transactional and promotional traffic differently, and many suppliers sell them on separate routes with their own rates. Ask for a price per traffic type and per destination, and never send marketing on a transactional route to save money, because the route can be suspended.
Need a route?
Send the destination, route type and target rate. We reply with what we can deliver.