Promotional vs Transactional SMS in India
The two kinds of business SMS in India side by side: what each is for, how its sender header reads, when it can be delivered and what it needs. Registration lets you send. It does not guarantee delivery.
- Transactional, per message
- ₹0.25
- Promotional, per message
- ₹0.15
- Window for a transactional reply
- 30 min
Checked against TRAI’s regulation, consolidated 21 May 2026
- NotifyTech AI Team
- 7 min read
- Compliance Guide
Two kinds of SMS, one registration
TRAI’s Telecom Commercial Communications Customer Preference Regulations, 2018 define the kinds of commercial SMS in India. The two businesses use most are transactional (a reply to something the customer just did) and promotional (anything that advertises). A third, service, carries information to existing customers; the DLT registration guide covers it.
Both types travel through the same registered parts: your entity, a header and a content template. What differs is what each may say, who may receive it and when. This guide is not legal advice, so check your DLT portal and TRAI’s documents for the current rules.
How do promotional and transactional SMS differ?
Both go through the same registered entity, header and template. They split on four things: what the message is for, the suffix on its header, when it can be delivered, and what it needs. Read the two lanes side by side.
One registered entity, header and content template
Both lanes start with the same registrations on a DLT portal. Today a header is 6 characters, shown with an operator prefix and a suffix for its type. Documents, fees and approval times are the portal’s own.
What it is for
Transactional
A reply to a transaction the customer started, within 30 minutes of it: an OTP, a payment or order confirmation, a refund notice.
Promotional
Advertising a product or service: an offer, a launch, a sale.
Header
Transactional
A registered header ending -T, so recipients can tell what kind of message it is.
Promotional
A registered header ending -P, so recipients can tell what kind of message it is.
Who can receive it
Transactional
Any customer it answers. Recipients’ promotional preferences do not block it.
Promotional
Recipients who have not blocked promotions, or who gave explicit consent. Scrubbing checks each number first.
When it can go
Transactional
Not held back by the promotional time-band settings.
Promotional
By default 10:00 to 21:00 without explicit consent.
Content rules
Transactional
No promotional content. If any is mixed in, the whole message is treated as promotional.
Promotional
An opt-out in the same message. A promotional template is fixed text, with no variable part.
Consent
Transactional
No explicit consent needed.
Promotional
Explicit consent is optional, and lets a message through irrespective of the recipient’s registered preferences.
Which type is my message?
Ask two questions. Is the message answering something the customer did within the last 30 minutes? Then it is transactional. Does it advertise anything? Then it is promotional, however it starts. These five messages are sorted the way TRAI’s own definitions sort them.
An OTP or login code
Transactional (-T). TRAI names OTPs from banks and from other businesses such as e-commerce and app logins.
A payment, order or refund confirmation
Transactional (-T) when it answers the customer’s transaction within 30 minutes. TRAI lists transaction alerts and confirmations, balance alerts after a transaction, and refund information.
A delivery update
Service (-S), not transactional. TRAI lists information about the delivery of goods or services among service messages, which need no explicit consent.
A sale, launch or offer
Promotional (-P). Anything that advertises a product or service is promotional.
An order confirmation with a sale banner
Promotional. If promotional content is mixed into a transactional or service message, the whole message is treated as promotional, including its opt-out requirement.
What should I check before every send?
Four checks cover what usually goes wrong. Each follows from TRAI’s regulation, and your DLT portal shows the exact process for registering each part.
Send only from a registered header
Commercial SMS may only use registered headers. A sender that is not registered can have its telecom resources suspended or disconnected.
Match a registered template
Each message is checked against its registered content template. Keep the fixed text identical and put only changing details, such as a name or an amount, in variables. A promotional template is fixed text.
Keep promotion out of -T and -S messages
One promotional line in a transactional or service message makes the whole message promotional. Send offers as separate promotional messages.
Offer an opt-out and keep consent records
A promotional message must offer the recipient an opt-out in the same message. If you send on explicit consent, register a consent template and record each recipient’s consent on your DLT portal.
What happens if a sender breaks the rules?
TRAI’s regulation works on access. A message that does not match is not delivered, a blacklisted header gets the sender’s traffic suspended, and repeat violations lead to a longer blacklisting. Anything beyond that depends on your access provider, so check your DLT portal.
A message that does not pass is not delivered
Before delivery, the target numbers are compared with each recipient’s preferences and consent. A promotional message to someone who has blocked promotions and has not consented does not go through.
A blacklisted header suspends your traffic
When a header is blacklisted for sending commercial communication against the regulation, the sender’s traffic is suspended. It resumes after the registrars have reviewed all your headers and templates, or seven days after the suspension, whichever is earlier.
Repeat violations mean a longer blacklisting
Repeat violations lead to the sender being blacklisted across all access providers for a minimum of one year.
When can each type be delivered?
Recipients’ promotional blocks do not stop a transactional message. They do apply to promotional ones, and by default four time bands are off for every recipient, which leaves 10:00 to 21:00 for a promotional SMS sent without explicit consent.
These are the defaults in TRAI’s regulation (Schedule II). Recipients can change their own settings, and your DLT portal shows how your account is set up.
A promotional SMS sent without explicit consent
- Off by default: 00:00 to 10:00 and 21:00 to 24:00
- Open by default: 10:00 to 21:00
- Transactional
- Recipients’ promotional blocks do not stop it. TRAI’s definition of unsolicited commercial communication excludes transactional messages.
- Promotional, no explicit consent
- Delivered to recipients who have not blocked promotions, by default between 10:00 to 21:00.
- Promotional, explicit consent
- A message sent on a recipient’s explicit consent is delivered irrespective of their registered preferences in the applicable category.
Frequently Asked Questions
Common questions about promotional and transactional SMS in India
References & Further Reading
TRAI’s own documents behind this guide
- Read the Regulations
TCCCPR 2018, consolidated
TRAI’s Telecom Commercial Communications Customer Preference Regulations as consolidated on 21 May 2026: the definitions of each message type, headers, consent and time bands. The gazetted text prevails.
- Read the Note
Headers assigned to Principal Entities
TRAI’s note of 16 June 2020 on header length and the operator and circle prefixes.
- Open the Page
TRAI: unsolicited commercial communication
TRAI’s page listing its regulations, directions and guidance on commercial communication and DLT.
Send each message as the type it is
NotifyTech AI’s transactional and promotional SMS run on TRAI DLT with approved templates. Talk to our team about your setup.