SMS API
Send single and bulk SMS messages programmatically using Exotel's SMS API. Supports transactional, promotional, and OTP messages with DLT compliance for India.
Base URL
https://<api_key>:<api_token><subdomain>/v1/Accounts/<account_sid>/Sms/send
Regional Endpoints
| Region | Subdomain |
|---|---|
| Singapore | @api.exotel.com |
| Mumbai | @api.in.exotel.com |
Capabilities
- Single SMS — Send a message to one recipient
- Bulk SMS (Static) — Same message to multiple recipients
- Bulk SMS (Dynamic) — Unique messages to different recipients (max 100 per request)
- URL Shortening — Shorten links and track clicks
- Delivery Status — Real-time webhooks for delivery confirmation
Rate Limits
| Limit | Value |
|---|---|
| API calls | 200 requests/min |
| Bulk SMS per request | 100 messages max |
DLT Compliance (India)
For sending SMS in India, you must register with a DLT (Distributed Ledger Technology) portal and provide:
- DLT Entity ID — Your registered entity ID (mandatory)
- DLT Template ID — Approved template ID (required for template-based messages)
- Sender ID — Approved header registered with DLT
note
DLT registration is mandatory for all SMS sent to Indian phone numbers as per TRAI regulations.
SMS Types
| Type | Description |
|---|---|
transactional | OTP, alerts, order updates — sent anytime |
transactional_opt_in | Transactional with user opt-in |
promotional | Marketing messages — time-window restricted |
Quick Start
- Get your API credentials from the Exotel Dashboard
- Register for DLT (India only)
- Use the Send SMS endpoint to send your first message