TRAI Update 2025: Introduction of Message Identifier in A2P SMS Headers
A New Era in SMS Transparency and Compliance Begins May 6th, 2025
In a move set to enhance message clarity and regulatory compliance, the Telecom Regulatory Authority of India (TRAI) has announced a new update that will impact all A2P (Application-to-Person) SMS communications across India. Starting tentatively from May 6, 2025, all telecom operators will implement a mandatory Message Identifier Suffix in SMS headers.
This new rule is part of TRAI’s continued efforts to improve transparency and help recipients easily distinguish between different types of messages — Promotional, Service, Transactional, or Government-related.
What’s Changing?
Introduction of an Identifier Suffix
All SMS headers (Sender IDs) used in A2P messaging will now end with a specific alphabetic suffix that reflects the nature of the message.
| Message Type | Suffix | Example SMS Header |
|---|---|---|
| Promotional | -P | AD-ARIHNT-P |
| Service | -S | VP-ARIHNT-S |
| Transactional | -T | BP-ARIHNT-T |
| Government | -G | EXEMPTED-G |
Template-Based Identifier Allocation
This suffix will be automatically determined by the DLT (Distributed Ledger Technology) platform based on the approved SMS content template. Once the content is scrubbed via DLT, the corresponding suffix will be appended to the SMS header.
Note: Only TRAI-exempted headers will be treated as government category and suffixed with -G.
Why Is This Update Important?
- Better Clarity for End-Users: Recipients can now instantly understand whether an SMS is promotional, transactional, or service-related.
- Enhanced Regulatory Compliance: Businesses using A2P messaging services must stay compliant to avoid disruptions.
- Fraud Prevention: Helps identify and reduce misleading or fraudulent messages by verifying authenticity.
- Improved Delivery Transparency: Telecom operators can better classify and prioritize message traffic.
How This Impacts You
If you’re a business owner, marketer, or organization using bulk SMS to connect with customers, your SMS headers will change automatically based on the message type defined in your approved DLT templates. There is no manual action needed for the suffix – it will be appended by telecom operators during the DLT message scrubbing process.
However, it’s highly recommended to recheck your DLT templates and ensure they are categorized correctly as Promotional, Service, or Transactional.
✨ Example Use Cases
- Retail Promotions:
Header →CP-BIGSALE-P
(Promotional offers, discounts, festive sales) - Appointment Reminders:
Header →CP-CLINICX-S
(Informing customers of scheduled services) - Banking OTPs:
Header →CP-HDFCBK-T
(One-time passwords, payment alerts)
Conclusion
This update by TRAI is a positive step toward better customer communication and cleaner message categorization. It also provides more visibility to end-users, letting them choose how to engage with messages based on their type.
At Arihant Global, we’re here to assist our clients through this transition and ensure all SMS communications remain DLT-compliant, secure, and optimized for success.
💬 Need Help or Have Questions?
Our team is ready to support you in managing your DLT SMS templates, header registrations, and ensuring smooth communication flow with your customers.
📞 Call Us: 0141-2942622
📧 Email: [email protected]
🌐 Visit: www.arihantglobal.in