Transactional SMS

Last updated: September 23, 2026

SMS sending via Zoho CPaaS allows you to send transactional messages such as OTPs, order confirmations, and account alerts directly to customer's mobile numbers through a simple REST API.

For businesses sending transactional SMS in India, compliance with the Telecom Regulatory Authority of India (TRAI) regulations is mandatory. Messages must be sent using a DLT (Distributed Ledger Technology)-registered Sender ID. To enable this service, you must first register your business on a DLT portal, get an approved Sender ID, and share the Sender ID details with Zoho CPaaS. Once verified, you can send transactional SMS to recipients in India.

This feature is currently supported for customers hosting their accounts in the IN DC.You can send transactional SMS from your registered sender to customers in India.

Pre-requisites

Before you can send transactional SMS through Zoho CPaaS, you must complete the following steps on your telecom operator's DLT portal:

Register your business entity on a DLT portal to obtain your 19-digit Principal Entity ID (PEID).
Register your Sender ID (a 6-character alphabetic code, for example ZOHOML) under the correct category — Transactional, Promotional, or Service.
Create a PE-TM chain by adding ZOHO CORPORATION PRIVATE LIMITED (telemarketer ID 1102631350000082951) as your Telemarketer Aggregator. Create two chain entries to ensure delivery through Zoho CPaaS's fallback mechanism.
Create and get the SMS templates approved also whitelist any URLs that appear in your message content. Shortened URLs are not permitted.
Once your DLT registration is complete, share your Sender ID details with Zoho CPaaS to complete verification.

Sender

A Sender is your core identity object in Zoho CPaaS. Every SMS you send goes out under a Sender, which holds your DLT-registered Sender ID and is linked to your API key. A Sender must be associated with at least one Agent before it can be used to send messages.

SMS templates

An SMS template in Zoho CPaaS defines the structure and content of your message, including fixed text and variable placeholders for dynamic content such as OTPs, order numbers, or recipient names. Every SMS sent through Zoho CPaaS must use a pre-approved template, otherwise you cannot send a message. Templates are created and managed directly in Zoho CPaaS and must comply with DLT guidelines before they can be used. Zoho CPaaS sends a test SMS to verify the template before approving it.

To send transactional SMS from Zoho CPaaS in India, the recipient's mobile number should be in the format: +91-XXXX-XXXXXX

Pricing

In order to send SMS notifications, you need to have sufficient credits in your account. Each time an SMS is sent, credits will be deducted from your account.

Messages up to 160 characters cost ₹0.18 per SMS.
Messages exceeding 160 characters are split into parts of up to 153 characters each, and each part is charged separately.