SMS Sender ID in India: Understand Headers, Prefixes & DLT

What is an SMS Sender ID?

An SMS Sender ID, also called an SMS header, identifies the business or entity associated with a message. A familiar, properly registered header helps recipients recognize the sender of service notifications, account alerts and other permitted business messages.

How do SMS prefixes work?

In India, SMS headers and their display formats are governed by applicable telecom and commercial communication requirements. The prefix shown with a header may identify the originating telecom provider and its licensed service area. The exact format and assignment process can depend on the applicable rules and operator systems.

Sender ID registration and DLT

Businesses sending regulated commercial SMS may need to complete Principal Entity registration and register applicable headers and message templates through the relevant telecom operator's DLT platform. The correct requirements depend on the message category and current regulations. Ensure that your sender header and content are approved before sending messages.

Understanding the header format

The legacy reference below illustrates a format often described as XY-ABCDEF: the prefix and separator are followed by a header assigned to a Principal Entity. Treat the tables as historical reference material, not as a current or exhaustive list of active operator codes. Verify present-day assignments and requirements with the relevant telecom operator before using any code.

Transactional and promotional messaging can follow different rules. Do not assume that a particular sender ID format, numeric header, delivery route or exemption applies to every message. Confirm the current requirements for your message type before launching a campaign.

Telecom provider prefix reference

The following legacy tables are retained from the existing page for reference. Some provider names, codes or service-area mappings may have changed since the source document was published.

Historical reference: service-provider codes (‘X’)  Verify current codes with the telecom operator
Sr. No.	Name of Service Providers	Code Allocated
1.	Aircel Ltd/ Dishnet Wireless Ltd	D
2.	Bharti Airtel Ltd/ Bharti Hexacom Ltd	A
3.	Bharat Sanchar Nigam Ltd	B
4.	Quadrant Televentures Limited	Q
5.	Mahanagar Telephone Nigam Ltd	M
6.	Reliance Communications Ltd	R
7.	Reliance Jio Infocomm Ltd	J
8.	Reliance Telecom Ltd	E
9.	Tata Teleservices Ltd/ Tata Teleservices (Mah)Ltd	T
10.	Vodafone Idea Ltd	V
11.	V-CON Mobile & Infra Private Ltd.	C
12.	BPL Mobile/Loop Telecom	L
13.	HFCL Infotel	H
14.	Idea Cellular Ltd., Aditya Birla Telecom Ltd.	I
15.	Shyam Telecom Ltd.	Y
16.	Spice Communications Ltd.	P
17.	Uninor / Telenor (Telewings Communications Services Pvt. Ltd.)	U
18.	Swan Telecom	W

Historical reference: service-area codes (‘Y’)  Verify current codes with the telecom operator
Sr. No.	Service Area	Code Allocated
1.	Andhra Pradesh	A
2.	Assam	S
3.	Bihar	B
4.	Delhi	D
5.	Gujarat	G
6.	Haryana	H
7.	Himachal Pradesh	I
8.	Jammu & Kashmir	J
9.	Karnataka	X
10.	Kerala	L
11.	Kolkata	K
12.	Madhya Pradesh	Y
13.	Maharashtra	Z
14.	Mumbai	M
15.	North East	N
16.	Orissa	O
17.	Punjab	P
18.	Rajasthan	R
19.	TamilNadu including Chennai	T
20.	UP-East	E
21.	UP-West	W
22.	West Bengal	V

Historical source document (published 2020; verify current applicability):
TRAI header-prefix reference PDF

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