Why business SMS in India now show -P, -S, -T or -G at the end of the sender name, what each one means and what it changes for senders.
If you have noticed sender names like JM-TXTNSM-T or VK-123456-P on your phone, you are seeing TRAI's header suffix rule. Under the amended Telecom Commercial Communications Customer Preference Regulations, operators started adding a one-letter suffix to every commercial SMS header from 6 May 2025.
What each suffix means
- -P (Promotional): offers, discounts and marketing. Only sent to customers who have not blocked promotional messages, and only during allowed daytime hours.
- -S (Service): updates linked to a service the customer uses, such as delivery updates or reminders, sent with implicit or explicit consent.
- -T (Transactional): messages triggered by a transaction, such as bank OTPs and debit alerts.
- -G (Government): messages from government bodies.
Who adds the suffix?
You don't. The operator adds it automatically when the message passes DLT scrubbing, based on the category of the content template it matches. That is why getting the template category right matters: the suffix customers see comes straight from it.
What it changes for your business
- Customers can now judge at a glance whether a message is an alert or an advert. Honest categories build trust; a marketing message sent as "service" damages it.
- Promotional messages are visibly marked, so make the first line worth reading.
- If your templates were registered in the wrong category, re-register them before customers start ignoring your alerts.
How TextNSMS handles it
Your templates are stored with their DLT category, and the dashboard shows which suffix each campaign will carry before you send. Learn more about DLT-compliant Bulk SMS or read our DLT registration guide.
Frequently asked questions
Do I need to change my header to add the suffix?
No. Operators add -P, -S, -T or -G automatically based on the category of the DLT template your message matches.
Why does my OTP show -T but my delivery update shows -S?
OTPs are transactional, while delivery updates are service messages. Each is registered under a different template category, and the suffix follows that category.
Related service
Bulk SMS with TextNSMS
Prepaid wallet, pay per message, DLT-compliant routes. Serving Delhi, Noida, Gurgaon and all of India.