While you will be using WebEngage to create all your SMS campaigns, the actual delivery of the message to your target audience is facilitated by an SMS Service Provider (SSP) like Twilio, Exotel, Plivo, mGage and so on.


Please Ensure That Your Website & Apps Are Integrated with WebEngage Before Proceeding

(Doing so will enable real-time personalization of messages sent to each user!)

SMS Marketing Concepts

Let’s quickly walk you through a few related concepts:

Transactional SMS

Messages that convey updates or information related to the user's lifecycle like account balance, payment received, account debited/credited, subscription expired/renewed, out for delivery, product dispatched/delivered, unable to deliver, and so on are generally classified as Transactional SMSes. Most users usually expect to receive such messages while performing certain actions on your app/website or offline.

Such texts override all international DND regulations, owing to their urgent nature and are usually sent through the SSP’s Transactional Messaging Pipeline.

Promotional SMS

Messages that are aimed at engaging users with offers, coupons or nudge users to perform a certain action like completing the purchase, continue streaming, try out a new service and so on are generally classified as Promotional SMSes.

Such text campaigns are strictly regulated by a national do not call list in several countries like India, Singapore, UK, Canada, US and are delivered through the SSP's Promotional Messaging Pipeline. Depending on your SSP, you could opt-in for a High-priority Promotional Messaging Pipeline to ensure timely message delivery.


Depending on the SSP you're using, you may need to whitelist the message body, personalization tokens (User’s Name, Order ID, Purchased Product, Account Number) and links for all your Transactional Messages. Whitelisting ensures that the message is delivered through the SSP's transactional pipeline as soon as possible, even if the user’s number is registered in a national do not call list.

This means that before you start sending Transactional SMSes, you will need to create a standard copy for each use-case and have it registered or whitelisted with your SSP. For example, let’s say that we’re whitelisting the following text:


Transactional SMS Template for Delivery Update

Hey {{user['system']['first_name']}},

Your Order ID, {{event['custom']['Order Placed']['custom']['Order ID']}} is out for delivery! Track it here: https://dummylink.com/track-order

  • {{user['system']['first_name']}} personalizes message to each user's registered first name

  • {{event['custom']['Order Placed']['custom']['Order ID']}} personalizes message to the latest order placed by each user

Then, while whitelisting the message, you will need to request your SSP for a standard code they use to identify the personalization tokens and links. This means that the actual message you whitelist would look something like this (depending on the codes used by your SSP):


Whitelisting Delivery Update SMS with an SSP

Hey #123#,

Your Order ID #123# is out for delivery! Track it here: @yxz

However, do keep in mind that any major deviation in the text being sent to your users, and the whitelisted text will cause the SMS to be treated as a Promotional Message.


You can think of SSPs as middle-men that transmit the message from WebEngage to the Mobile Network Operators of your users. We have partnered with several global SSP leaders to help make SMS marketing a seamless process for you.

SSP Integration

As shown below, you can integrate multiple SSPs with your project by navigating to Integrations > Channels > SMS.

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Here, you will find a list of all the SSPs for which we provide ready-to-use integrations. And if you have already added a few SSPs to your project, then you will be able to view the configuration details in the first half of this section. For example, in the visual below, you can see that two Twilio accounts have been integrated.

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SSP Setup

Please select an SSP from the left navigation panel (Channel Configurations > SMS) to continue configuration.

Setting Up SSP for Sending Different Types of SMS Campaigns

Depending on the SSP you’re using, you may need to purchase separate licenses/Sender IDs for sending Transactional and Promotional Messages, respectively. Thus, while creating an SMS campaign, please be mindful of the fact that the SSP selected at Step 3: Message has been set up to send the SMS Type selected at Step 1: Audience. A mismatch between the two may cause your campaign to fail.

Managing Configuration

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As shown above, integrated SSPs are listed under the section, Your SMS Service Provider List. You can choose to Edit or Delete the integration anytime you like by accessing the Actions menu placed on the extreme right.

The Actions menu also indicates the unique Webhook URL you can add to your WSP dashboard to ensure that delivery status notifications (sent, failed, queued, delivered) are tracked under campaign stats in your WebEngage dashboard.

Editing an SSP

You can choose to edit configuration details in cases where incorrect details were entered during configuration, or the SSP updated some details post-integration.

As shown below, select Edit from the Actions menu, make your changes, and click Save.

Updating account credentials for an existing SSP (click to enlarge)

Deleting an SSP

Deleting an integration will cease campaign delivery for all Running and Upcoming campaigns where the respective SSP was selected for sending it. In such cases, you will be prompted by the following message.

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Thus, please ensure that no existing campaigns are dependant on the SSP (you intend to delete) for sending SMSes to your users.

As shown below, select Delete from the Actions menu, and click the Delete button in the pop-up to confirm your decision.

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TRAI DLT Regulations for SMS Marketing in India

(Applicable only if you are sending messages to users located in India via domestic messaging pipeline. International messaging routes remain unaffected.)



  • Whitelisting templates for all messages.

  • Registering the business entities and Sender IDs used for SMS marketing.

  • Registering user consent or SMS opt-in status.

In an effort to control promotional spam, SMS fraud, and unsolicited messaging the Telephone Regulatory Authority of India (TRAI) has enforced new guidelines for SMS marketing. It mandates the whitelisting of all SMS templates and registration of your company's entities, Sender IDs (Headers), and user consent in a centralized DLT portal, provided by Indian mobile operators.

  • This is applicable for sending both, Transactional and Promotional campaigns. Additionally, a third campaign type has been introduced by TRAI - Service (Implicit & Explicit). You can find more details on the respective DLT portals while whitelisting message templates.

  • November 19, 2020, is the tentative deadline for registration. Failing to do so will cause mobile operators to cease the delivery of all your messages to their end-users.

  • Additionally, TRAI also prohibits all kinds of SMS marketing between DND hours from 21:00 Hrs. to 10:00 Hrs. Bank/ Financial Transaction OTPs are the only exception that can be conveyed via SMS during these hours.

Emphasis on Customer Consent & Preferences: The new regulations grant complete control to your customers over multiple aspects (in addition to existing DND regulations). This includes:

  • Opting-out of receiving SMSes from your brand.

  • Opting-in to receiving promotional SMSes from your brand even if a user is registered in the national DND list.

  • Specify a time window, in a day, for receiving promotional messages. (Messages sent outside this window will fail to get delivered due to DLT Scrubbing).

DLT Registration

Here's a quick overview of the process:

Step 1: Register your Business to get a Unique PE ID
Step 2: Register your Sender IDs
Step 3: Whitelist all SMS templates to get DLT Template ID for each one
Step 4: Register your PE ID and DLT Template ID with SSP to comply with DLT Scrubbing Rules (WebEngage simplifies this process for select SSPs!)

Step 1: Register Business Entity to Generate Unique PE ID


You Can Register on the Following DLT Portals

Tata Tele Services

Once registered, you will be assigned a Principal Entity ID (PE ID) which must be used for registering your Sender IDs and Message Templates. Please get in touch with your SMS Service Provider to understand if you need to register with all the aforementioned operators.

Attaching PE ID to each SMS sent by you: As per TRAI's regulations, your PE ID must be passed in the message payload of each SMS sent to your users. Failing to do so will cause delivery failure owing to DLT Scrubbing by the mobile network provider. Here's how you can go about it:

  • Option 1: Update your API integration with the SSP to include PE ID in the SMS message payload.

  • Option 2: Add PE ID to WebEngage dashboard.

    • At WebEngage, you can easily add your PE ID while configuring the following SSPs in your dashboard. We'll ensure that it's relayed to your SSP for each SMS campaign sent by you: Exotel, Gupshup, Infobip, Kaleyra, MSG91, ValueFirst

    • If you are using an SSP other than the ones listed above, then please get in touch with your account manager asap to obtain more clarity!

Step 2: Register Sender ID

Depending on your use-case, you can choose to register your custom Sender Name/ Sender ID/ Headers as Transactional or Promotional directly with the mobile network providers. Please check the respective definitions on the DLT portals before you begin the process.

Step 3: Whitelist Message Templates to Generate Template ID

(Here's a template creation guide to help you get started)

Your SMS templates can be whitelisted on the DLT portals mentioned above, under any of the following categories:

  • Transactional (Reserved only for bank OTPs.)
  • Service-Implicit / Service-Inferred (To be used for all other transactional campaigns.)
  • Promotional (Requires proof of user consent & includes messages that sell products/services.)
  • Service-Explicit (Requires proof of user consent & includes messages that recommend products/services.)

You will receive a unique DLT Template ID for each SMS template approved by the portals.


Including Personalization Variables in SMS Templates for Whitelisting

  • All details such as name, date, account number, OTP, codes, transaction ID, a/c numbers, URLs, and so on are considered as personalization variables during the whitelisting process.

  • Each variable can be replaced by the placeholder, {#var#} in your message There is no upper limit on the number of variables you add to a template.

  • While it's mandatory for Transactional and Service-Implicit messages to include personalization variables, these can be excluded from Promotional and Service-Explicit messages.

Attaching DLT Template ID to each SMS sent by you: As per TRAI's regulations, w.e.f Feb 1, 20201 the Template ID must be passed in the message payload of each SMS sent to your users. Failing to do so will cause delivery failure owing to DLT Scrubbing by the mobile network provider. Here's how you can go about it:

  • Option 1: Register all your approved SMS templates manually with your SSP. (Depending on your SSP, you may need to update your APIs too.)

  • Option 2: Add DLT Template ID to WebEngage dashboard

    • We have partnered with Exotel, Gupshup, Infobip, Kaleyra, MSG91 and ValueFirst to help you manage template registration. You can simply add the DLT Template ID while creating an SMS campaign, we'll ensure that the parameter is passed to your SSP for each SMS.
    • If you are using an SSP other than the ones listed above, then please get in touch with your account manager asap to obtain further clarity!

DLT Scrubbing

TRAI has deemed it mandatory for all SMS marketers to provide their PE ID (w.e.f Nov 1, 2020) and DLT Template ID (w.e.f Feb 1, 2021) in the message payload for each SMS sent to a user. All SMSes will be subject to DLT scrubbing at the mobile network provider's end. This means that if either parameter is missing from the message payload, then the SMS will fail to get delivered.

At WebEngage, we have partnered with Exotel, Gupshup, Infobip, Kaleyra, MSG91 and ValueFirst to help you pass these parameters in the message payload of each SMS, directly through your dashboard. (So that you continue all your SMS marketing activities unhindered!)

  • PE ID can be added while integrating any of the aforementioned SSPs.

  • DLT Template ID can be added while creating an SMS campaign (only if any of the aforementioned SSPs are selected at Step 3: Message).


Please Note

Owing to TRAI's regulations, you may incur an additional DLT scrubbing charge of Rs. 0.25 per SMS. Please get in touch with your SSP for more details on their revised bulk SMS/ Promotional and transactional messaging rates.

Please feel free to drop in a few lines at [email protected] in case you have any further queries. We're always just an email away!

Updated 2 months ago


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