Transactional vs promotional SMS — what's the difference?
India's TRAI regulations force you to pick a category up front. Picking wrong gets your traffic blocked.
Every SMS sent to an Indian number must be tagged with one of four DLT categories: transactional, service-implicit, service-explicit, or promotional. The category controls who you can send to, when, and at what price.
The quick rule
- Transactional — OTPs and critical alerts tied to a user action. Allowed 24x7 to everyone, even DND-registered numbers.
- Service-implicit — status updates for something the user initiated (order shipped, refund processed). Allowed 24x7 to everyone.
- Service-explicit — reminders and nudges on a subscribed service. Allowed 24x7 to users who opted in.
- Promotional — offers, deals, newsletters. Only allowed to non-DND numbers, only 9am–9pm IST.
Browse other help categories
Getting started
Create your SMSLocal account, add INR credits to your wallet, complete DLT registration, and send your first compliant SMS, WhatsApp, or OTP in under fifteen minutes.
WhatsApp Business API
Complete guide to WhatsApp Business API — onboarding, Meta template approval, chatbot flow setup, shared team inbox, quality rating management, and conversation analytics.
AI WhatsApp Agents
Train your AI WhatsApp agent on your own knowledge, sync your product catalogue, configure handoff triggers, and serve customers across twelve Indian languages.
OTP & Transactional
Priority routing to the fastest carrier, automatic retry and failover logic, idempotency keys to prevent double-sends, and WhatsApp OTP fallback when SMS is slow or fails.
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