sms campaigns

What is TRAI's Regulation for Including Message Type Suffixes in SMS Headers?

Starting on May 6, 2025, the Telecom Regulatory Authority of India (TRAI) mandates telecom providers in India to append a suffix to the sender header of all application-to-person (A2P) SMS messages. This suffix will indicate the type of message:

P – Promotional

S – Service

T – Transactional

G – Government-authorized

For example, a header like JD-ZYLKER will now appear in your recipient's inbox as XY–ZYLKER–P, where "XY" is the operator and circle code, and "P" indicates a promotional message.

This update aims to enhance transparency, reduce spam, and standardize SMS communication. Businesses do not need to make any manual changes when sending bulk SMS (promotional, transactional, or customer service alerts). Telecom providers will automatically add the suffix based on the type of SMS you're sending during DLT scrubbing.

When can I send SMS campaigns to Indian contacts?

According to TRAI, you can send commercial messages can be sent only between 0900 to 2100 hrs. Any promotional or commercial messages send before 9 A.M. or after 9 P.M. (IST) will be rejected.

Can I start sending SMS messages as soon as registering content template?

No, you can start sending messages only after your content template is approved by the registrar or the status of your template in your mobile operator turns to "Approved" state.

Is it mandatory to add a brand name in the content template?

Yes, it is mandatory to add your brand/company name in the message so that receivers can identify the sender of the message. It should be explicitly mentioned in the SMS body.

Example template:

Hello {#Var#},

Claim your orders by sending this coupon code {#Var#}.

<Brand-name>.

What are the message types that can be used for framing content template?

There are two message types that can be used: Text and UNICODE. The messages that are framed in the English language are considered as Text and all messages framed in other languages are considered as UNICODE.

Can I map multiple headers with a content template?

Yes, you can associate multiple headers with a single content template. However, it is better not to do so. It may appear suspicious to the reviewers and they might reject it. If the message appears slightly irrelevant to any of the header or selected type, the template will be rejected.

How do I add variables in content template?

You can add variables in the content template using the symbol {#var#}. Values like amount, date, account number, OTP, customer names and transaction ID have to be replaced with variables.

You cannot use more than two variables continuously, and each variable can hold up to a maximum of 30 characters only.

I want to choose a relevant header, but it is not directly related to my company or product name, what should I do?

You can upload a document to prove the co-relation between your company or product and the Sender ID (Header). If the registrar is satisfied with the document of proof, your Header (Sender ID) may get approved.

How should I frame my header?

To send promotional SMS messages, you need to choose the promotional header type. For this type, you can set a unique six-digit header for your service. However, there are certain rules while choosing your header or sender ID. Depending on your company's industry, the first digit can vary.

Refer the table below to recognize your industry and set the first digit of your header accordingly.

Business Category	Header must start with
Banking/Insurance/Financial products/Credit cards	1
Real Estate	2
Education	3
Health	4
Consumer Goods and Automobiles	5
Communication/Broadcasting/Entertainment/IT	6
Tourism and Leisure	7
Food and Beverages	8
Others	0

What are the different types of Header?

Headers are classified mainly into two categories: Promotional and Others (Transactional, Service Implicit, Service Explicit). To send marketing SMS messages, you need to choose the promotional category. If your header type and the intent in message don't match, your request might be rejected.

What is Header in DLT?

Header is a combination of six characters representing your brand or company. Depending on the purpose of the SMS, the header can be classified as Promotional, Transactional, Service Implicit and Service Explicit.

For sending marketing or promotional SMS, such as offers, discounts, or promotions, you need to choose the "Promotional" category and choose a six-digit numeric sender ID, which will be prefixed with your business. Along with that, you need to attach proof of your business for verification.

Why haven't I received my entity ID in two days?

Ensure that you have :

Received OTP (one-time pin) on the registered mobile number and email address.

Clicked the email verification link for confirmation.

If you meet both the requirements mentioned above, then you may write your query to the support team of the operator that you have registered with. You will need to provide your Application Number, Company Name, and Registered Email ID in the mail.

Why is my Entity registration request for DLT rejected?

Your registration request can be rejected for the following reasons:

If the documents submitted are not in the prescribed format.

If the details provided while registering does not match with the documents submitted on the DLT portal.

If the provided email address or other contact details are invalid or incorrect.

Does a Principal Entity have to be registered separately on each platform?

No, Principal Entity does not have to be registered separately on each DLT platform. If you have already registered your business and have an Entity ID, you can use the same in other telecom operators.

Most mobile networks enable you to use your existing Entity ID though it was registered with a different mobile operator.

What is Letter of Authorization in DLT?

Letter of Authorization must be submitted while registering on the DLT platform. It has to be provided on the company letter head where the owner has to provide authority to the individual who is registering on the DLT portal on company’s behalf.

It is mandatory to submit the Letter of Authorization while registering. It can be written in word document and uploaded as a file in the Authorization Document Field.

What are the documents required to get Entity ID?

For registering as a Principal Entity and acquiring an Entity ID, you need to upload the following documents:

For Identity Proof: PAN Card

For Address Proof: Passport/Voter ID/Driving License

For Business Entity Proof: GST Registration, Certificate of Incorporation, TAN, Trade License, Company PAN Card

What is Business category?

This refers to the industry your business belongs to. You can choose this from the list of options provided by the mobile operators while registering to get an entity ID.

What is the Entity type?

This is the type of your organization, which needs to be mentioned while submitting the form. It can be Pvt. ltd, Ltd, Govt, and so on.

What are the steps for DLT Registration?

DLT registration process consists of three steps. Once you've completed these three steps, then you can send bulk SMS messages to your customers in India.

Steps:

Header (Sender ID) registration

Content Template Registration - Template ID

Who is the Access Provider?

Access Providers are the mobile operators or telecom operators such as Vodafone, Jio, BSNL, Satzilio who provides DLT registration service. They play a major role in the new DLT framework and will assist in the regulation process.

Learn more about the DLT registration process in:

Jio

BSNL

Vodafone Idea

Satzilio

Who is referred to as Principal Entity?

Principal Entity is the company/organization who is sending SMS messages to its clients and customers. It can be an individual, sole proprietor, partnership firm, or any private, public, or government organization who wants to communicate with their clients using Bulk SMS Service.

When you are registering on the DLT platform, your company is the principal entity in the DLT registration process

Will my SMS delivery to Indian customers be affected if I don't register on DLT platform?

TRAI has mandated the DLT registration process for people who want to send bulk marketing SMS messages and transactional SMS messages in India. So, all bulk SMS sending services need to comply with this.

If you are trying to send SMS messages to Indian customers without getting registered on the DLT platform, Zoho Campaigns will not be able to process those SMS messages, so your SMS will not be delivered to Indian contacts.

Is DLT registration mandatory to send SMS campaigns?

TRAI has a mandated DLT registration process for people who want to send bulk marketing SMS messages and transactional SMS messages in India. DLT registration is issued to bring forth a transparent SMS sending system and control SMS spam and fraudulent activities done using SMS. It helps marketers to align with their contact's interests and have a spam-free structure to their SMS messagees.

This means you need to get registered to send SMS messages in India. Learn more about the 10 DLT registration process.

Who is the regulator of the DLT platform?

The Telecom Regulatory Authority of India (TRAI) will govern the DLT operations and establish regulatory compliance to safeguard consumer interests.

What is DLT and why should I register for 10DLT?

DLT is a blockchain-based registration system that stores bulk SMS sender related data, such as entities, sender IDs, and message templates, in a secure manner.

Earlier, only the bulk SMS providers were required to register with TRAI. With the updated rules, whoever wants to send promotional or transactional SMS to their customers needs to be DLT registered.

Can I preview my SMS campaign before sending it?

Yes, you can view how your SMS campaign will look in your recipient's inbox using the Preview option in Zoho Campaigns.

To preview your SMS campaign:

From the Navigation toolbar, click Campaign and select SMS Campaigns.

Click the Campaign you want to preview, and scroll down.

Can I include short URLs or trackable links in SMS campaigns?

Yes, you can add short URLs and links to your SMS campaign. Once the campaign is sent, you can analyse how users have interacted with the link from the SMS campaigns reports section.

Are there any prerequisites for sending SMS campaigns own gateway?

While sending SMS campaigns using Zoho Campaigns' SMS gateway, please keep the following in mind:

You must have sufficient SMS credits.

If you are sending SMS to recipients in India, you must have a valid DLT registration.

If you are sending SMS to recipients in the USA, you must have a 10DLC registration.

If you are not using Zoho Campaigns' SMS gateway, you can use any of the supported third-party SMS gateways. In such cases, there are no restrictions from our end.

Is it mandatory to add an unsubscribe link in the sms campaign?

No, it is not mandatory to add an unsubscribe link in your SMS campaign. However, we strongly recommend including one. Even if you don’t add it, the recipient’s network provider will automatically provide them with an option to stop receiving messages from you. If a recipient finds your messages irrelevant and has no way to opt out, they might mark you as spam using the link provided by their network. This can damage your sender reputation over time. So, it’s always better to give recipients the option to unsubscribe rather than continuing to message them and risking being marked as spam.

Can I personalize the sms campaigns I send?

Yes, Zoho Campaigns lets you personalize your SMS campaign using merge tags. To include merge tags in your SMS, click inside the content section of the SMS configuration page and press Control+M.

What is the character limit for my SMS campaign content?

The maximum character limit is 1,000 characters. However, we recommend keeping your message under 200 characters to ensure better readability. In case you're using a third-party SMS gateway, the character limit may vary depending on their policies.

Learn more about creating and sending SMS campaigns using Zoho Campaigns

Can I use emojis in my sms campaign?

Yes, Zoho Campaigns lets you add emojis to your SMS campaigns. Even though there are no restrictions on the number of emojis you use, we recommend you use them in moderation to avoid clutter and improve message clarity.

You can add emojis by clicking the emoji icon in the SMS content section on the Configure SMS Content page.

What happens if my message exceeds the SMS character limit?

If your message exceeds the character limit, you won’t be able to save the content. To proceed further with the campaign, you'll have to reduce the character count to the allowed limit.

Is it mandatory to verify the sender number before sending an SMS campaign?

This depends on the country you’re sending the campaign to. For example, if you're sending SMS to recipients in India, DLT registration is required. For the USA, 10DLC registration is mandatory. Other countries may have different regulations. We recommend you check the compliance requirements for the specific country before sending your SMS campaign.

To which countries can I send SMS campaigns using Zoho Campaigns?

You can send SMS campaigns to the USA, Canada, and India using Zoho Campaigns' own SMS gateway.

For other countries, you can send campaigns by integrating with third-party SMS gateways supported by Zoho Campaigns.

What happens if I send SMS to contacts without consent?

Sending SMS to contacts without their consent can tarnish your sender ID reputation. If recipients find your messages irrelevant, they may mark you as spam with their network provider. Over time, this can significantly damage your sender reputation. To maintain trust and avoid being flagged as spam, always obtain prior consent and include an unsubscribe option in your messages.

How is SMS pricing calculated in Zoho Campaigns?

SMS credit consumption varies based on the recipient’s country. For example, sending an SMS to the USA or Canada consumes 4 credits per message. You can calculate the pricing for your target countries using Zoho Campaigns' SMS pricing calculator.

Do unused SMS credits expire?

No, unused SMS credits will be carried forward to the next billing cycle.

Can I check how many SMS credits I have left?

Yes, you can check your SMS credit balance on Zoho Campaigns.

To do so:

Click the Settings icon at the top right corner of the screen.

Click Overview under SMS.

You'll be able to view your SMS credits.

Will duplicate numbers receive the SMS multiple times?

No, Zoho Campaigns will automatically ignore duplicate contacts while sending the SMS campaign. Each unique number will receive the message only once.

What changes does the latest SMS Campaigns module migration entail?

Zoho Campaigns has made few important changes to the SMS campaigns setup. Here are couple of the highlights of this update:

A brand new SMS unsubscribe feature.

A default Zoho Campaigns SMS gateway to send SMS campaigns. We support sending SMS to US, Canada and India using the Zoho Campaigns SMS gateway.

To use our SMS gateway, you need to move the contact number details of your contacts to the Mobile number field. We'll help you seamlessly migrate the data to the default field "Mobile number" during the migration.

Can I send transactional messages using Zoho Campaigns SMS gateway?

No, you will not be able to send transactional messages. You can only send marketing and promotional messages for now.

How to delink a long code?

You need to contact support@zohocampaigns.com to delink a long code to initiate the delinking process. It is to be noted that you have to inform the support team 5 days before your pricing renewal date to delink a long code.

How do I purchase long codes using Zoho Campaigns?

Zoho Campaigns supports long codes in the USA, and Canada. You can purchase a long code via Zoho Campaigns and use that code to trigger SMS campaigns directly from our product.

Long codes can be purchased when you are buying SMS credits. Once you've paid for long code, you can select a preferred code and start using it.

To start using a long code in Zoho Campaigns:

1. Click Settings on the top-right corner of the screen.
Settings icon - top right

2. Click Sender Details under SMS.
sms sender details

3. Click Register Now.

4. In the pop up that appears, select country and choose long code. If you have chosen USA or Canada, click Next. If the country you have selected is India, then enter the Entity ID and Sender ID details, and click Register. Register new long code

5. Select long code type and type in your preferences about your number and click Search Numbers.

6. Choose a number from the list of available numbers based on your preferences.
Choose long code

7. Click Yes, I want to own in the upcoming pop up.

What is long code?

Long codes, or 10DLC (10 Digit Long Code), are the normal 10 digit phone numbers that can be used to send bulk SMS and make voice calls. It is somewhat similar to the phone numbers we have for personal use, except these 10DLCs are used for business purposes.

It is also referred to as A2P (Application to Person) 10DLC as business messages are sent to prospective customers via an application

How does SMS unsubscribe work?

Recipients who opt out using the unsubscribe link in SMS will not receive further SMS and email communications from the account. These contacts will be marked as opt out from all marketing communications on our end.

What will happen to the draft SMS campaigns after migration?

It will be adopted to the new model automatically. Phone numbers will be pulled from the default Mobile Number field. If the recipient details are in other fields, please update that data in the Mobile Number field to send the campaign to all the selected recipients.

How do I send SMS campaigns if I don't have accounts with SMS gateways?

You can use the new Zoho Campaigns in-house gateway to send SMS campaign to your contacts. You can purchase SMS credits, add a sender address, and send SMS campaigns to contacts in US, Canada and India.

Does this update affect my existing scheduled SMS campaigns?

Scheduled campaigns/live journeys of existing accounts will not be affected with respect to this update. However, you cannot edit these campaigns/SMS components after the update. If you want to edit the recipient fields of a scheduled campaign or any SMS component, you need to clone the campaign and reschedule the edited campaign or add a new SMS component.

Why are my contacts being ignored or considered invalid?

E.164 is a numbering plan followed internationally to ensure each device on the Publicly Switched Telephone Network (PSTN) has a globally unique number. Its important to follow the E.164 format when importing contacts to your Zoho Campaigns account. SMS campaigns sent to contacts whose numbers do not align with the E.164 format often do not go through. Rules you need to follow for a phone number to be E.164 qualified include:

The maximum length of phone numbers is 15 digits.

The format of the phone number should comprise a country code (1 to 3 digits) and subscriber number including area code (up to 12 digits).

A sample phone number adhering to the E.164 plan would be similar to +12345678901, where [+1] is the country code, [234] is the area code, and [5678901] is the subscriber's phone number. Ensure that all your contacts are saved in the format as shown in the image below.
E.164 format

Given below are some of the examples of E.164 numbers:

E.164 format	Country code	Country	Subscriber Number
+12468097531	1	US	2468097531
+16789012345	1	Canada	6789012345
+919876543210	91	India	9876543210

While trying to import contacts into Zoho Campaigns, contacts that are not saved according to the E.164 format will either be ignored or considered invalid. You will not be able to send SMS campaigns to such contacts, hindering your business communications with them.

What are the changes associated with the new SMS model?

The new SMS model contains the following changes:

A new in-house SMS gateway will be available to send SMS campaigns.

Country and number fields cannot be selected. Necessary data will be retrieved from Mobile Number field by default.

We support SMS unsubscribes with the recent update.

You can choose the FROM address format with the latest update. Two kinds of mobile sender address format: Long code and Alphanumeric sender ID will be supported.

When is the new model of SMS going live?

The new SMS model will go live on August 18, 2022. New users who sign up after this date will get the new SMS updates by default. Existing users will be given time until September 20th, 2022 to switch to the new model.

10DLC

10DLC mandatory to send SMS campaigns to Canada recipients?

No, it is not mandatory to have a 10DLC registration to send SMS campaigns to your recipients in Canada. However, you'll need it if you want to send SMS to recipients in the USA.

What will happen if you do not have sufficient credits in your account for the 10DLC campaign monthly fee?

We will send you two warning emails and inform you to update the SMS credits to pay for the 10 DLC Campaign. If you don't add sufficient number of credits before the date of payment, your 10 DLC Campaign will be de-registered from our end. You'll have to do the registration process again.

What is the price to do the 10DLC registration with Zoho Campaigns?

You will pay for 10DLC registration in the form of SMS credits. Zoho Campaigns supports three types of legal entities for a brand: private, non-profit, and government, and it costs 1664 SMS credits (or 4 dollars) for brand registration.

10DLC campaign registration will require a registration fee and monthly fee after requesting for registration. The cost varies based on your campaign use case.

How should I deregister 10DLC campaign?

If you want to deregister a 10DLC campaign, then you need to contact support@zohocampaigns.com. It might take few days for a 10DLC campaign to be de-registered, so contact support a few days prior to the subscription payment period.

What happens if my brand request is rejected?

The reason for a brand not being verified is mostly because of an error in the information provided. If your brand is not verified, review all of the brand information for any typos, EIN that was entered incorrectly and other mistakes.

If you are not able to determine the possible reason for rejection, please reach out to support@zohocampaigns.com

What happens if my 10DLC campaign request is rejected?

Please follow all best practices and be careful when you are requesting for a 10 DLC Campaign. If your 10 DLC Campaign is not approved within a week or it gets rejected, please reach out to support@zohocampaigns.com. Our team will help you resolve issue in the existing submission or to make a new request.

What are some best practices while creating a 10DLC campaign?

It is better to be careful while submitting a 10DLC campaign to get it approved without any hassles. Some of the best practices for a 10DLC campaign are:

Maintain consistency between sample message and actual messages you would be sending. If there will be embedded links or phone number in your messages, ensure it is in the template as well.

Establish your brand by mentioning it's name. Try to use your brand name or brand domain in shortened links you add in the template and use cases.

Make sure the context of your sample template and use cases are the same. If you've framed a template for a marketing message and enter a transactional message in use case, the request will not be approved.

Ensure the links you have in the use cases and templates are working.

Keep records of your source and if you want to customers to signup using link in your SMS, then mention clearly that they will be subscribing to your messages.

Include opt-out message in your sample templates. This, will be checked during the review process.

How long does it take for my brand and 10DLC campaign registration to be approved?

Brand registration takes 7 days, and 10DLC campaign verification takes 14 days. If your 10DLC campaign is not verified within this time period, please contact support@zohocampaigns.com.

How many use cases do I need to register?

This depends on your brand or company's requirements. Some companies may only need to register one campaign use case, and some may need more than one.

For example, if you are a company that sends OTPs to validate users while logging in to your application, but you also send marketing messages, you should register two campaign use cases.

What is a campaign use case?

In the 10 DLC campaign registration process, use case refers to the purpose or type of message you want to send to your contacts.

If you want to send SMS campaigns, choose Marketing.

Zoho Campaigns supports the following use cases:

Agent franchise

Charity

Conversational

Delivery notification

Emergency

Fraud alert

Marketing

Social

Public service announcement

Polling voting

What are the steps involved in 10 DLC registration?

Before you start the registration process, you'll need to have sufficient SMS credits for your brand and 10DLC campaign registration.There will be a one time and registration costs for both steps and it will be charged as soon as you register. Payment will be debited as SMS credits from your organization.

You can refer here to determine how many credits you might require for your specific case.

10 DLC registration involves three steps:

Registration of the brand

Registration of a 10DLC campaign (along with use case)

Associate long code with a campaign

What is the purpose of 10 DLC?

The objective of 10 DLC is to protect consumers from unwanted spam, as well as enabling businesses to better connect with their customers. This will also enhance deliverability as 10DLC allows for higher messaging throughput than normal long code traffic.

How is the 10 DLC registration beneficial?

There are some advantages to using a 10DLC-approved long-code:

These long codes can support moderately large volumes of text messages compared to the long codes that aren't 10DLC-approved.

They are cost-effective alternatives to dedicated short codes. It is beneficial to businesses that can’t afford a short code number or don’t send sufficient messages to justify paying for a short code.

Pre-approved 10DLC numbers have better deliverability. Messages sent on these numbers are more likely to reach the recipient than with regular local long codes.

What happens if I don't register for 10DLC?

You won't be able to send SMS messages unless you are 10DLC-verified, so we recommend that you complete the 10DLC registration process to assure better deliverability.

Which countries follows 10DLC registration process?

If your organization sending SMS messages to contacts to USA using long codes, then 10DLC registration is applicable to your organization.

What is 10DLC?

It is also referred to as A2P (Application to Person) 10-Digit Long Code (10 DLC), as business messages are sent to prospective customers via an application. They are approved by mobile network operators in the US for A2P SMS messaging.

What happens when I submit my brand and 1DLC campaign data for registration?

After submission, we will pass this data to The Campaign Registry (TCR) for verification of your data. TCR is the reputation authority for business messaging on 10DLC and they verify all the A2P 10 DLC registration submissions and provides approval. It is mandatory to get their approval before you can send 10 DLC verified SMS messages.

What are the steps that I need to take after brand and 10DLC campaign verification?

You need to associate your verified 10DLC campaign with a long code. This means that the SMS messages you send with the associated long codes are 10DLC-verified and they will have improved deliverability and throughput rate.

SMS Campaigns - Online Help | Zoho Campaigns