What is a Header ID or Sender ID?

A Header ID (or Sender ID) is a unique alphanumeric or numeric string that appears as the sender name in business SMS. It acts like a verified caller ID for your messages, ensuring customers know exactly who's reaching out. As per TRAI rules, every Header ID must be registered on the DLT platform.

What are the types of Header IDs?

There are four types: 1) Promotional Headers (6-digit numeric for promotional messages), 2) Transactional Headers (3-6 alphanumeric characters for OTPs, alerts), 3) Service Implicit Headers (alphanumeric, triggered by customer actions), 4) Service Explicit Headers (alphanumeric, requires consent for marketing messages).

Why is Header ID registration important?

Header ID registration ensures regulatory compliance with TRAI norms, builds transparency and trust with customers, prevents spam and fraud, and enables seamless SMS communication without messages being blocked or flagged.

TRAI DLT Header ID - Sender ID Registration India-TECHTO NETWORKS

📱 Header ID & Sender ID Guide

Master TRAI DLT regulations and create a trusted brand identity for your bulk SMS campaigns

What is a Header ID (Sender ID)?

A Header ID, also known as a Sender ID, is the unique identifier that appears as the sender's name when recipients receive your SMS messages. Think of it as your business's digital signature – instead of seeing a random mobile number, your customers see your brand name or a recognizable code like "AMAZON," "HDFC," or "ZOMATO."

In India, as per TRAI (Telecom Regulatory Authority of India) regulations, every business entity must register their Header ID on the DLT (Distributed Ledger Technology) platform before sending any commercial SMS. This mandatory registration ensures transparency, reduces spam, and builds trust between businesses and consumers.

🔒

Secure & Verified

TRAI-approved identification ensures authenticity

🎯

Brand Recognition

Customers instantly recognize your business

📈

Higher Open Rates

Branded senders get 40% more engagement

⚖️

100% Compliant

Meets all regulatory requirements

Header IDs can be either alphanumeric (combination of letters and numbers, 3-6 characters) or numeric (6 digits for promotional messages). The format you choose depends on the type of communication you're planning to send to your customers.

Why Header IDs Are Critical for Your Business ?

🚫 Regulatory Compliance

TRAI mandates that all commercial SMS in India must be sent through registered Header IDs. Non-compliance can result in hefty penalties, service suspension, and legal consequences. Businesses caught sending unregistered SMS face fines up to ₹10 lakhs and potential blacklisting from telecom operators.

🏆 Brand Identity & Trust

In an era of phishing and spam, customers are increasingly cautious about unknown senders. A registered Header ID with your brand name builds immediate recognition and trust. Studies show that SMS messages from branded senders have 40-50% higher open rates compared to generic numeric senders. When customers see "YOURBANK" instead of "+919876543210," they're more likely to read and act on the message.

🛡️ Spam Prevention & Security

The DLT registration process includes verification of your business entity, ensuring that only legitimate businesses can send messages. This ecosystem-wide approach has significantly reduced SMS spam in India. For customers, this means fewer fraudulent messages. For businesses, it means your genuine communications won't be confused with spam, protecting your reputation.

📊 Improved Delivery Rates

Telecom operators actively filter and often block messages from unregistered senders. With a properly registered Header ID, your message delivery rates can reach 95-98%, compared to just 60-70% for unregistered senders. This directly impacts your campaign ROI and customer reach.

💼 Professional Communication

Imagine receiving an OTP from "BK-123456" versus "VERIFIED" or a delivery update from a random number versus "FLIPKART." Professional Header IDs elevate your brand's image, making every interaction feel polished and trustworthy. This small detail can significantly impact customer perception and loyalty.

Types of Header IDs: Choose the Right One

Format: 6-digit numeric code (e.g., 123456, 765432)

Usage: Marketing campaigns, sales offers, promotional events, new product launches, discount announcements

Time Restrictions: Can only be sent between 9 AM to 9 PM (as per TRAI guidelines)

Consent Required: Yes – customers must explicitly opt-in through documented consent

DND Compliance: Must respect Do Not Disturb registry; messages won't be delivered to DND-registered numbers

Category Classification

The first digit of promotional headers indicates the business category:

1xxxxx: Banking, Insurance, Financial Products, Credit Cards
2xxxxx: Real Estate
3xxxxx: Education
4xxxxx: Health & Pharmaceuticals
5xxxxx: Consumer Goods & Automobiles
6xxxxx: Communication, Broadcasting, Entertainment, IT
7xxxxx: Tourism & Leisure
8xxxxx: Food & Beverages

Example Messages:

"FLASH SALE! Get 50% off on all electronics. Shop now at www.example.com Use code SAVE50. T&C apply. From: 165432"

"Mega Diwali Sale! Up to 70% OFF on fashion & lifestyle. Visit your nearest store or shop online. Valid till 10th Nov. - 567890"

Important Notes:

Promotional headers cannot be used for transactional or service messages
Messages must contain clear opt-out instructions
Cost per SMS is typically higher for promotional messages
Lower priority in delivery queue during network congestion

Format: Alphanumeric, 3-6 characters (e.g., AMAZON, HDFC, PAYTM)

Usage: OTPs, payment confirmations, booking confirmations, account alerts, password resets

Time Restrictions: Can be sent 24/7 (no time restrictions)

Consent Required: No – these are service-critical messages

DND Compliance: Exempt from DND restrictions as they're essential for service delivery

Key Characteristics:

Must be purely informational and transaction-related
No marketing or promotional language allowed
Typically triggered by user actions or system events
Time-critical information that users need immediately
Cannot include discount codes, offers, or promotional URLs
Must be essential for completing a service or transaction

Common Use Cases:

One-Time Passwords (OTPs) for authentication
Banking transaction alerts and balance updates
Flight/train booking confirmations and PNR details
E-commerce order confirmations
Payment success/failure notifications
Account security alerts (password changes, login attempts)
Utility bill payment confirmations
Hotel check-in/check-out confirmations

Example Messages:

"Your OTP for login is 456789. Valid for 10 minutes. Do not share with anyone. - YOURAPP"

"Rs 5000 debited from A/c XX1234 on 05-Nov-25. Avl Bal: Rs 45,000. - HDFC"

"Your booking is confirmed. PNR: 1234567890. Train: 12345, Date: 10-Nov-25. - IRCTC"

"Payment of Rs 1,500 received successfully. Transaction ID: TXN123456789. Thank you! - PAYTM"

Critical Warning:

Even a single promotional line in a transactional message can result in your header being blocked or permanently reclassified. Maintain strict separation between transactional and promotional content.

Format: Alphanumeric, 3-6 characters

Usage: Product updates, policy changes, subscription newsletters, value-added information

Time Restrictions: Can be sent 24/7, but recommended during business hours (9 AM - 9 PM)

Consent Required: Yes – explicit customer consent needed and must be documented

DND Compliance: Must respect DND preferences; requires documented consent

Understanding Service Explicit

Service Explicit messages provide information or value to customers but require their explicit, documented permission. These messages bridge the gap between pure service updates and promotional content. While they may contain offers or marketing elements, their primary purpose is to inform customers about services, products, or policy updates related to their existing relationship with your business.

Key Characteristics:

Requires documented customer consent (opt-in)
Can contain informational content with marketing value
Related to existing service or product usage
May include offers, but not purely promotional
Customer must be able to opt-out at any time
Typically sent to existing customer base
Focuses on adding value through information

Common Use Cases:

Product feature updates and enhancements
Policy changes, terms & conditions updates
Premium service upgrade offers to existing customers
Loyalty program benefits and tier updates
Insurance policy renewal reminders with benefits
Credit card spend-based offers and milestone rewards
Educational content related to purchased products
Seasonal tips and best practices for service usage
Cross-sell opportunities for complementary services
Program anniversary benefits and special privileges

Consent Requirements:

Unlike Service Implicit, you must obtain and document explicit customer permission. This can be through:

Checkbox during account registration or purchase
Separate opt-in form for marketing communications
SMS-based consent confirmation (double opt-in)
Written agreements with consent clauses
Email confirmation with SMS opt-in links
Call center verbal consent with recording
Mobile app permission settings

Important: Maintain records of consent including date, time, method, and IP address where applicable.

What Makes It Different from Promotional?

While both require consent, Service Explicit headers are for customers with whom you have an existing relationship. The messages provide service-related value alongside promotional content.

Promotional headers, on the other hand, are used for cold marketing to prospects or general promotional campaigns without the service relationship context. Service Explicit is warmer, more personalized, and based on existing trust.

Example Messages:

"Your insurance policy premium is due on 15th Nov. Pay online by 10th Nov and get 5% cashback + extended coverage benefits. - INSURE"

"New Feature Alert! Your PREMIUM account now includes free international transfers. Activate at www.example.com/activate - BANK"

"You've reached Gold tier in our loyalty program! Enjoy 2x rewards on all purchases this month. Terms apply. - RETAIL"

"Important: Our Terms of Service have been updated. New privacy features added for your protection. Review at www.example.com/terms - APPNAME"

"Your credit card crosses Rs 50K spend! You've unlocked complimentary airport lounge access. Details: www.example.com - CARD"

Format: Alphanumeric, 3-6 characters

Usage: Order updates, delivery notifications, appointment reminders, service alerts

Time Restrictions: Can be sent 24/7

Consent Required: Implicit – based on existing customer relationship

DND Compliance: Exempt from DND restrictions due to service relationship

Understanding "Implicit Consent"

Service Implicit messages are triggered by a customer's action or existing service relationship. The key distinction is that the customer's interaction with your service automatically implies their consent to receive related updates.

For example, when someone orders food online, delivery updates are service implicit messages – the customer's action of placing an order implies consent for updates about that specific order.

Key Characteristics:

Based on an ongoing service relationship with the customer
Triggered by customer's own actions or requests
Provides updates relevant to services already subscribed or purchased
No separate consent documentation required
Must be directly related to the service being used
Cannot be purely promotional in nature

Common Use Cases:

E-commerce delivery status updates and tracking information
Food delivery order preparation and dispatch notifications
Cab/ride booking confirmations and driver details
Appointment reminders for booked services
Subscription renewal reminders
Service maintenance notifications
Account activity alerts based on customer's profile settings
Warranty and service period expiry reminders
Utility meter reading schedules
Package delivery attempts and rescheduling

Important Distinctions:

The "implicit" nature means that when a customer engages with your service (places an order, books an appointment, subscribes to a service), they automatically consent to receive relevant updates. However, this doesn't give you carte blanche – messages must remain strictly relevant to the specific service interaction.

Example Messages:

"Your order #123456 is out for delivery. Expected arrival: 2-3 PM. Track: www.example.com/track - ZOMATO"

"Reminder: Your appointment with Dr. Smith is scheduled for tomorrow at 10 AM. Clinic Address: XYZ Medical Center. - CLINIC"

"Your ride is arriving in 2 minutes. Driver: John, Car: KA-01-AB-1234. - UBER"

"Your broadband service will undergo maintenance on 10-Nov from 2-4 AM. Inconvenience regretted. - AIRTEL"

"Your electricity bill of Rs 2,450 is due on 15-Nov-25. Pay online to avoid late charges. - BESCOM"

COMPARISON TABLE: HEADER TYPES

Feature	Promotional	Transactional	Service Implicit	Service Explicit
COST	Lower	Higher	Higher	Standard
DELIVERY PRIORITY	Lower	Highest	High	Medium
CONTENT	Purely promotional	Purely transactional	Service-related	Mixed (info + offers)
USE CASE	Marketing & Sales	Banking Critical Alerts	Service Updates	Info + Value-added
DND Delivery	Blocked	Allowed	Allowed	Blocked Except Consent
CONSENT	Explicit Required	Not Required	Not Required	Explicit Required
TIMING	10 AM - 8 PM	24/7	24/7	10 AM - 8 PM
FORMAT	6-digit numeric	Alphanumeric 3-6	Alphanumeric 3-6	Alphanumeric 3-6

STEP-BY-STEP HEADER ID REGISTRATION PROCESS

1. Choose Your Telecom Service Provider (TSP)

Select a DLT-registered TSP like Airtel, Vodafone Idea, Jio, BSNL, or MTNL. Each TSP has its own DLT portal. You'll need to register as a Principal Entity first if you haven't already.

Principal Entity Registration requires:

Business registration documents (Certificate of Incorporation, Partnership Deed, etc.)
GST Registration Certificate
PAN Card of the business
Authorized signatory's ID and address proof
Letter of Authorization on company letterhead

2. Login to DLT Portal

Access your chosen TSP's DLT portal using your Principal Entity credentials. Navigate to the SMS Headers section, typically found under "Header Management" or "SMS Services."

Portal URLs:

Airtel: dlt.airtel.in
Vodafone Idea: www.vilpower.in
Jio: trueconnect.jio.com
BSNL: dltconnect.bsnl.co.in

3. Navigate to Header Registration

Click on

"Header SMS Registration"

"Register New Header."

You'll be presented with a form to enter header details. Ensure you have all required information ready before starting.

4. Select Header Type & Category

Choose the appropriate header type:

Promotional
Transactional
Service Implicit
Service Explicit

For promotional headers, select your business category which determines the first digit of your header. Choose carefully as this cannot be changed later.

5. Enter Header Details

Provide your desired Header ID. Follow these guidelines:

For Alphanumeric Headers:

3-6 characters only
Use your brand name or abbreviated version
Only uppercase letters and numbers allowed
No special characters, spaces, or lowercase letters
Must match your registered business entity or trademark

For Numeric Headers (Promotional):

System will auto-generate based on your category
First digit determined by business category
Remaining 5 digits assigned sequentially

6. Upload Supporting Documents

Submit required documents based on header type:

Mandatory Documents:

Business registration certificate
GST Registration Certificate
Letter of Authorization (on company letterhead with authorized signatory)
ID proof of authorized signatory (Aadhaar/PAN/Passport)
Address proof of business

Additional Documents (if applicable):

Trademark registration certificate (for branded names)
Domain ownership proof (if header matches website)
Previous header approval (for reusing across operators)

Document Requirements:

All documents must be clear, legible scans or PDFs
File size typically limited to 2MB per document
Accepted formats: PDF, JPG, PNG
Documents must be valid and not expired

7. Submit for Approval

Review all details carefully before submission:

Verify header spelling and format
Check that selected type matches intended usage
Ensure all documents are uploaded correctly
Confirm contact details for communication

Submit your registration request. You'll receive an acknowledgment with a reference number for tracking. Save this reference number for future correspondence.

8. TSP Validation Process

The TSP registrar verifies your documents and header details. What they verify:

Business entity legitimacy
Document authenticity
Header name appropriateness
Compliance with naming guidelines
Match between header and business name

They may request clarifications or additional documents.

Common reasons for rejection:

Mismatch between header name and business entity
Incomplete or unclear documents
Header name too generic or misleading
Trademark issues or similarity to existing brands
Non-compliance with naming conventions

9. Receive Approval Notification

Upon approval, you'll receive:

Email confirmation with header details
SMS notification to registered mobile
Unique header ID reference number

The header is now active and ready for use.

10. Cross-Operator Usage

The best part: Once approved by one TSP, you can use the same Header ID across all other telecom operators in India without separate registrations.

BEST PRACTICES FOR HEADER ID MANAGEMENT

📝 Smart Naming Conventions

Do's:

Use your brand name or abbreviated version (e.g., FLIPKART, AMAZON, HDFC)
Keep it memorable and easy to recognize
Ensure consistency across all communication channels
Use uppercase for better visibility

Don'ts:

Avoid generic names like INFO, ALERT, or UPDATE
Don't use misleading names
Avoid special characters or spaces
Don't register headers too similar to competitors

🎯 Multi-Brand Strategy

If you operate multiple brands or services, register separate Header IDs for each. This helps customers distinguish between different product lines and improves brand clarity. For example, a company might use MAIN for core services and MAINDL for delivery updates.

🧪 Testing & Monitoring

Before launching major campaigns, send test messages to verify delivery, formatting, and sender ID display across different devices and operators. Monitor delivery reports regularly and maintain a blacklist to exclude opted-out numbers.

📋 Template Linkage

Remember that your Header ID must be linked with approved message templates on the DLT platform. Each message you send must match a registered template associated with your header. Mismatches result in message blocking.

🔄 Regular Compliance Audits

Periodically review your header usage, message templates, and consent records. TRAI regulations evolve, and staying updated prevents compliance issues. Set quarterly reminders to check for regulatory updates.

FREQUENTLY ASKED QUESTIONS

1. How is a Header ID different from a normal mobile number ?

Aspect	Header ID	Mobile Number
Replies	Cannot receive replies directly	Can receive replies
Cost	Standard SMS rates	Standard SMS rates
Usage	Commercial/business SMS only	Personal or business
Registration	Must be registered on DLT	No registration needed
Trust Factor	High - registered and verified	Low - could be anyone
Recognition	Instantly recognizable brand name	Anonymous, unknown number
Format	Alphanumeric (BRAND) or 6-digit (123456)	10-digit number (+919876543210)

2. What are the different types of Header IDs and which one should I choose?

Answer: There are four types, each serving specific purposes:

1. PROMOTIONAL (6-digit numeric, e.g., 123456)

Use for: Sales campaigns, marketing offers, new product launches
Timing: 9 AM - 9 PM only
Consent: Explicit consent required
Best for: Cold marketing, promotional campaigns

2. TRANSACTIONAL (Alphanumeric, e.g., HDFC)

Use for: OTPs, payment alerts, booking confirmations
Timing: 24/7
Consent: Not required
Best for: Critical, time-sensitive notifications

3. SERVICE IMPLICIT (Alphanumeric, e.g., ZOMATO)

Use for: Order updates, delivery notifications, appointment reminders
Timing: 24/7
Consent: Implicit (through service usage)
Best for: Service-related updates

4. SERVICE EXPLICIT (Alphanumeric, e.g., INSURE)

Use for: Policy updates with offers, product information with benefits
Timing: 24/7 (recommended business hours)
Consent: Explicit required
Best for: Existing customer communications with mixed content

How to choose:

Sending OTPs or payment alerts? → Transactional
Sending marketing offers to prospects? → Promotional
Sending order tracking updates? → Service Implicit
Sending insurance renewal with offers to existing customers? → Service Explicit

3. Can I use one Header ID for all types of messages?

Answer: No, absolutely not. Each header type is strictly regulated:

Promotional headers are numeric only - cannot be used for transactional messages
Transactional headers cannot contain any promotional content - even a single promotional line will get your header blocked
Service headers must match their purpose - implicit for triggered updates, explicit for consent-based communications

Why this matters: Using a transactional header for promotional content is one of the most serious violations. TRAI's AI systems actively monitor for this, and penalties are severe:

Immediate header blocking
Fines up to ₹10 lakhs
Potential blacklisting from all operators
Legal proceedings in serious cases

Best practice: Register multiple headers for different purposes. Most businesses need at least 2-3 headers.

4: How many Header IDs can I register?

Answer: There's no fixed limit on the number of Header IDs you can register. You can register as many as your business needs.

Common scenarios:

Single Header (Small businesses):

One brand, one type of communication
Example: Local restaurant with only delivery updates

2-3 Headers (Growing businesses):

BRAND (Transactional) - for OTPs, payment confirmations
BRAND1 (Service Implicit) - for order updates
156789 (Promotional) - for marketing campaigns

5-10 Headers (Medium enterprises):

Different headers for different product lines
Separate headers for different communication types
Regional variations of brand names

10+ Headers (Large enterprises):

Multiple brands under one company
Different services requiring distinct identification
Various departments (sales, support, billing)

Best practices:

Don't over-register - maintain only what you actively use
Use clear naming conventions to distinguish headers
Document the purpose of each header
Regularly audit and deactivate unused headers

5. Can I use my website domain as a Header ID?

Answer: Not directly, but you can use a variation:

Not Allowed:

EXAMPLE.COM (dots not permitted)
WWW.BRAND (special characters like dots)
HTTP://SITE (special characters)

Allowed:

EXAMPLE (without the .com)
BRAND (if it matches your domain brand)
EXMPLE (abbreviated version)

Requirements:

Must be 3-6 characters (alphanumeric only)
No special characters, spaces, or dots
Should match your registered business entity
For trademarked domains, provide trademark certificate

Tip: If your domain is YourBusiness.com, register "YRBIZ" or "YBUS" as your header - something recognizable but compliant with format requirements.

6. Can I register a Header ID without GST registration?

Answer: Generally, GST is mandatory, but there are exceptions:

Exempted Entities:

Government Departments
- Central government offices
- State government entities
- Municipal corporations
- Provide department registration documents
NGOs and Charitable Trusts
- Registered under Section 80G/12A
- Provide trust deed and registration certificate
- Show 501(c)(3) equivalent status
Educational Institutions
- Recognized schools and universities
- Provide educational registration certificates
- Show affiliation documents
Small Businesses Below GST Threshold
- Annual turnover under ₹20 lakhs (services) or ₹40 lakhs (goods)
- Provide business registration documents
- Submit turnover declaration affidavit
- Provide bank statements as proof
Agricultural Businesses
- Direct agricultural producers
- Provide land ownership documents
- Show agricultural business proof

Alternative Documents (if GST not applicable):

Udyog Aadhaar/Udyam Registration
Shop and Establishment License
Professional Tax Registration
Trade License
Income Tax Returns
Bank account statements showing business transactions

Important: Requirements vary by TSP. Check with your chosen telecom provider's DLT portal for specific requirements.

7. What happens if my Header ID registration gets rejected?

Answer: Don't panic - rejections are common and usually easily fixable.

Common Rejection Reasons:

Incomplete Documentation (40% of rejections)
- Issue: Missing documents or unclear scans
- Solution: Resubmit with all required clear documents
- Timeline: 3-5 days to resolve
Header Name Issues (25% of rejections)
- Issue: Generic names (INFO, ALERT), misleading names, too similar to existing brands
- Solution: Choose a specific, brand-related name
- Timeline: 5-7 days (new header selection and approval)
Document Mismatches (20% of rejections)
- Issue: Name on documents doesn't match application
- Solution: Ensure exact name matches across all documents
- Timeline: 2-4 days
Trademark Conflicts (10% of rejections)
- Issue: Header name conflicts with registered trademark
- Solution: Provide trademark certificate or choose different name
- Timeline: 7-14 days (depends on trademark verification)
Signature Issues (5% of rejections)
- Issue: Signature on LOA doesn't match ID proof
- Solution: Resubmit with matching signatures
- Timeline: 2-3 days