Quick Answer
Transactional SMS in India is a non-promotional message a business sends in response to a customer's own transaction, such as an OTP, payment confirmation or order alert, within 30 minutes of that transaction (as per TRAI's latest TCCCPR amendment). It carries a -T header suffix, reaches DND numbers 24/7 and must match a DLT template with typed variables. Ongoing account updates go as service SMS (-S). SMSGatewayHub delivers both on Pay As You Go pricing with a 99.9% uptime SLA.
What counts as transactional SMS today?
Under TRAI's latest TCCCPR amendment, operators append a suffix to every header so recipients can see the message type, for example VM-ABCDEF-T. Pick the category that matches your message before you register the template.
| Category | Header suffix | When to use it | DND & timing |
|---|
| Transactional | -T | Response to a transaction the customer just initiated, sent within 30 minutes: OTPs, payment and purchase confirmations, login codes, refund initiated. | Reaches DND numbers, 24/7 |
| Service (implicit / inferred consent) | -S | Updates to existing customers about a product or service they use: delivery status, EMI and bill reminders, balance alerts, appointment reminders, warranty and security alerts. | Reaches DND numbers, 24/7, no promotional content allowed |
| Promotional (incl. former service explicit) | -P | Offers, cross-sell and marketing. Service explicit templates have now been moved into this category. | DND scrubbing and consent apply; promotional time window |
| Government | -G | Central or state government and TRAI-exempted bodies only. | Exempt from preference blocking |
Mixing any offer or marketing line into a transactional or service message makes it promotional. Compare categories in detail on service explicit vs service implicit SMS and see how suffixes appear on SMS sender IDs.
What changed in the latest TRAI and DLT rules?
Four rule changes now decide whether a transactional message is delivered or rejected at DLT scrubbing.
Header suffixes (-T, -S, -P, -G)
Now applied by every operator. Your sender ID stays the same, but customers now see the message type. Register transactional and service content in the right category or it will be labelled -P.
Typed variables replace {#var#}
New templates must tag each value as {#numeric#}, {#alphanumeric#}, {#url#}, {#urlott#}, {#cbn#} or {#email#}. See converted examples on our DLT sample templates page.
Whitelisted links and numbers only
URLs, app links and callback numbers inside a message must be registered as CTAs on DLT. Unregistered links and generic public short links are rejected.
Service explicit moved to promotional
Messages that needed explicit consent now travel as -P promotional. Keep transactional and service templates free of offers so they keep 24/7 DND delivery.
Why SMSGatewayHub
Why choose SMSGatewayHub over other SMS providers?
Transactional SMS is only as good as its delivery, compliance and billing. Here is what sets SMSGatewayHub apart when you compare bulk SMS providers in India.
Latest DLT changes handled for you
Our team converts {#var#} templates to typed tags, registers your URL and callback CTAs and maps the new IDs. DLT priority support
Multi-operator routing with failover
Traffic is routed across operators with automatic failover, giving 2-6 second typical delivery and a 99.9% uptime SLA.
Certified security
ISO 27001, ISO 9001:2015, SOC 2 and VAPT tested, which matters for banks, fintech and healthcare. Trust Center
Trusted since 2009
10,000+ registered businesses and 2,000+ enterprise clients, with 24/7 support and a toll-free sales line, 1800 102 1822.
| Question to ask any SMS provider | SMSGatewayHub |
|---|
| Am I charged for undelivered messages? | No. You pay only for delivered SMS. |
| Who updates my templates for the new variable-tagging rule? | Our DLT team converts, re-registers and maps them for you. |
| Are delivery reports real operator reports? | Yes, live operator delivery reports in the panel and API. See delivery reports |
| What happens if one operator route slows down? | Traffic automatically fails over to another operator route. |
| Which security certifications do you hold? | ISO 27001, ISO 9001:2015, SOC 2 and VAPT tested. |
| Can I test before I buy? | Yes, start with 1,000 free SMS credits. Create a free account |
Comparing a specific provider? See our MSG91 alternative page or read how to audit an SMS provider's delivery reports.
Transactional SMS use cases by industry
Each card links to a dedicated industry page with message samples and DLT tips.
DLT-compliant transactional SMS template examples
Every changing value now carries a typed tag. Amounts go without commas so they pass {#numeric#}; every link or number must be a whitelisted CTA.
| Message (what the customer sees) | DLT template (typed-variable format) | Suffix |
|---|
| 482913 is your OTP to log in to ABC App. Valid for 10 minutes. Do not share it with anyone. - ABC | {#numeric#} is your OTP to log in to ABC App. Valid for {#numeric#} minutes. Do not share it with anyone. - ABC | -T |
| Payment of Rs.2499 received for order ORD58213. Thank you for shopping with ABC Store. | Payment of Rs.{#numeric#} received for order {#alphanumeric#}. Thank you for shopping with ABC Store. | -T |
| Your order ORD58213 is out for delivery today. Track: https://abc.in/t/58213 - ABC Store | Your order {#alphanumeric#} is out for delivery today. Track: {#url#} - ABC Store | -S |
| Dear Rahul, your EMI of Rs.4500 is due on 05 Nov. For help call 18001234567 - ABC Finance | Dear {#alphanumeric#}, your EMI of Rs.{#numeric#} is due on {#numeric#} {#alphanumeric#}. For help call {#cbn#} - ABC Finance | -S |
| Your appointment with Dr. Mehta is confirmed for 14 Oct, 11:00 AM. - City Clinic | Your appointment with Dr. {#alphanumeric#} is confirmed for {#numeric#} {#alphanumeric#}, {#numeric#}:{#numeric#} {#alphanumeric#}. - City Clinic | -S |
Need the full rulebook? Read the DLT template registration process and the blog on TRAI's mandatory variable tagging update.
How to start sending transactional SMS
Register on DLT
Register your business as a Principal Entity with an operator DLT portal. Our team guides you through DLT registration.
Get your header
Register a 6-character alphabetic sender ID under the transactional or service category.
Register templates and CTAs
Submit templates with typed variables and whitelist every URL and callback number. Use the sample templates as a guide.
Connect SMSGatewayHub
Map template IDs in your panel and send through the HTTP API, HTTPS API or SMPP.
Track and optimise
Watch live delivery reports and fix failures with our DLT error codes guide.
Transactional SMS resource map
Everything related to transactional SMS on SMSGatewayHub, grouped by what you need to do next.
Transactional SMS vs promotional SMS: which do you need?
Frequently Asked Questions
What is transactional SMS in India under the latest TRAI rules?
Under TRAI's latest TCCCPR amendment, a transactional message is sent by a business in response to a transaction the customer initiated, within 30 minutes of that transaction. Examples are OTPs, payment confirmations and login codes. These messages carry a -T header suffix and reach DND numbers 24/7.
What is the difference between -T and -S SMS?
-T marks transactional messages tied to a transaction the customer just made. -S marks service messages to existing customers, such as delivery updates, EMI reminders or balance alerts. Both reach DND numbers at any time; neither may contain promotional content.
Can transactional SMS be sent to DND numbers?
Yes. Transactional (-T) and service (-S) messages are delivered to all numbers, including those on the DND list, around the clock. Only promotional (-P) messages are filtered by DND preferences and consent.
Do I need to change my existing DLT templates?
Yes, if they still use the generic {#var#} placeholder. Templates must now tag each variable as {#numeric#}, {#alphanumeric#}, {#url#}, {#urlott#}, {#cbn#} or {#email#}, and every link or callback number must be a whitelisted CTA. SMSGatewayHub can convert and re-register them for you.
Can I add an offer to a transactional SMS?
No. Any promotional line turns the message into promotional SMS, which gets a -P suffix, DND filtering and time restrictions. Keep offers in a separate promotional template.
What does transactional SMS cost with SMSGatewayHub?
SMSGatewayHub uses Pay As You Go pricing: you buy credits as needed and pay only for delivered SMS; exact rates depend on volume and route, see https://www.smsgatewayhub.com/pricing or talk to sales on 1800 102 1822. You can also estimate spend with the SMS cost calculator.
How fast is transactional SMS delivered?
SMSGatewayHub's multi-operator routing delivers transactional SMS in 2-6 seconds in typical conditions, backed by a 99.9% uptime SLA and live delivery reports.
Send compliant transactional SMS today
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