TRAI Introduces Mandatory Variable Tagging for SMS Templates: What Businesses Need to Know

The Telecom Regulatory Authority of India (TRAI) has introduced an important compliance update that directly impacts all businesses using DLT-based SMS services for transactional and promotional messaging. As per the latest directive, Principal Entities (PEs) are now mandatorily required to define and tag all variable placeholders at the time of SMS template registration on the DLT platform.

This update applies to customers using VIL POWER DLT services and is aimed at strengthening the integrity, transparency, and security of SMS communications across India. In this article, we break down what the update means, why it matters, and how businesses can prepare to stay compliant without disrupting message delivery.

Understanding the Regulatory Update

Traditionally, SMS templates on DLT platforms allowed variables to be added without strict control over the type of data inserted during message submission. This flexibility, while convenient, opened the door to misuse—especially in promotional and misleading communications.

To address this, TRAI has mandated a structured variable tagging mechanism, ensuring that each variable used in an SMS template is explicitly mapped to a predefined tag that defines:

• The data type of the variable

• Its intended purpose

• The acceptable format during message submission

This means businesses can no longer use open-ended variables. Every placeholder must now be validated against its approved tag before the SMS is delivered.

What Is Mandatory Variable Tagging?

Mandatory variable tagging requires businesses to identify and label each variable in an SMS template using standardized tags provided by the DLT platform. During message submission, the system will allow only those values that match the approved tag type.

If the submitted value does not align with the tagged data type, the SMS may be rejected at the operator level, resulting in delivery failure.

This change applies to all new SMS templates registered on the platform once the feature goes live.

Available Variable Tags and Their Usage

Below are the variable tags introduced under this update and their recommended use cases:

1. {#numeric#}

Used for strictly numeric values, such as:

• One-Time Passwords (OTPs)

• Transaction amounts

• Counts or numeric references

Example Template:
Your OTP for login is {#numeric#}. Do not share it with anyone.

Sample Value:

748392

2. {#alphanumeric#}

Used for mixed data types, including:

• Reference IDs

• Ticket numbers

• Booking IDs

• Addresses or descriptive values

Example Template:
Your service request ID is {#alphanumeric#}. Our team will contact you shortly and deliver your parcel on {#alphanumeric#}.

Sample Values:

SRV9821AB

11B Worli Mumbai 120022

3. {#url#}

Used exclusively for website URLs, such as:

• Order tracking links

• Customer portals

• Payment pages

Example Template:
Track your order here: {#url#}

Sample Value:

https://track.company.com/order123

4. {#urlott#}

Used for OTT platforms or mobile app download links, including:

• WhatsApp click-to-chat links

• App store redirections

Example Template:
Download our mobile app from {#urlott#} to manage your account.

Sample Value:

https://wa.me/1XXXXXXXXXX?text=YourMessage

5. {#cbn#}

Used for callback or support contact numbers

Example Template:
For assistance, call us at {#cbn#}.

Sample Value:

1800123456

6. {#email#}

Used for email addresses mentioned in SMS content

Example Template:
For support, write to us at {#email#}.

Sample Value:

support@company.com

Implementation Timeline

• The mandatory variable tagging feature will be available for new template registrations starting 22nd January 2026 (tentative).

• All newly registered templates must comply with this requirement from day one.

• Guidance related to scrubbing, editing, or migrating existing templates will be communicated separately by the operator.

Businesses are advised not to wait until enforcement begins and should start aligning internal processes immediately.

Why This Update Matters for Businesses

This regulatory enhancement is designed to:

• Prevent misuse of variable fields in SMS content

• Improve consumer trust in SMS communications

• Reduce spam, phishing, and misleading messages

• Enforce higher accountability among brands

While the update adds an extra compliance step, it ultimately leads to a cleaner and more reliable messaging ecosystem.

How Businesses Can Prepare for Compliance

To avoid disruptions in SMS delivery, businesses should take the following steps:

1. Review Template Creation Processes

Ensure all future SMS templates clearly identify and tag each variable before submission on the DLT portal.

2. Update Internal Systems & APIs

Modify backend systems, APIs, and campaign workflows so that variable values strictly match the approved tag definitions.

3. Train Technical and Business Teams

Sensitize marketing, IT, and compliance teams about the new requirements to avoid accidental non-compliance.

4. Perform Pre-Submission Validation

Implement internal checks to validate variable formats before sending messages to the operator.

Final Thoughts

The introduction of mandatory variable tagging by TRAI marks a significant step toward more secure and transparent SMS communications in India. While it requires businesses to adapt their workflows, early compliance will ensure uninterrupted message delivery and stronger customer trust.

Non-adherence to this directive may result in SMS rejection or delivery failure, making it critical for businesses to act proactively.

For any clarification or support regarding VIL POWER DLT services, customers can reach out to support@vilpower.in or call +91 9619 500 900.

Staying compliant today ensures smoother communication tomorrow.