DLT Registration for SMS in India
Complete Guide

What is DLT?

DLT (Distributed Ledger Technology) is TRAI's mandatory registration system for commercial SMS in India. It was introduced to curb unsolicited messages — spam, phishing, fraud — and has been compulsory for all businesses since 2022.

The system works like this: before you can send a single commercial SMS, you register your business (called a Principal Entity), your sender names (called Headers or Sender IDs), and every message format you plan to send (called Templates, each with a Template ID). When you send an SMS, the telecom operator checks the message against your registered templates character by character. If it matches, the message is delivered. If it doesn't — even by one extra space or emoji — it is silently dropped.

Who needs DLT registration?

Every business, organisation or individual that sends commercial SMS in India — whether promotional, transactional or service messages. This includes:

• E-commerce companies sending order confirmations and delivery updates
• Clinics and hospitals sending appointment reminders
• Banks and fintech companies sending OTPs and account alerts
• Retailers sending festive offers and discount campaigns
• Schools and coaching centres sending batch updates and fee reminders
• SaaS companies sending verification codes and product notifications
• Any business using an SMS provider like Fast2SMS, Plivo, MSG91, or Twilio to reach Indian numbers

If you are sending only personal, non-commercial messages from your own phone, DLT does not apply. Everything else requires it.

What you need before you start

Step-by-step registration process

You register on any one DLT operator portal. All portals are synchronised — your entity, headers and templates propagate across every telecom network automatically. You do not need to register on multiple portals.

Step 1 — Register your entity

1. Go to any DLT portal listed above and click "Register as Principal Entity" (sometimes labelled "Enterprise Registration").
2. Fill in your business details — company name, PAN, GSTIN, registered address, authorised signatory name and contact.
3. Upload your PAN card, GST certificate, company registration certificate and authorised signatory letter.
4. Pay the registration fee — approximately ₹5,000 + ₹900 GST = ₹5,900. This is a one-time payment. You do not pay it again for renewals, headers or templates.
5. Submit. The portal reviews your documents and issues a 13-character Principal Entity ID (PE ID) starting with "TM" — for example, TM-1234567890. This usually takes 1 to 3 working days.

Step 2 — Register your sender IDs (headers)

1. Log into your DLT portal with your PE ID.
2. Go to "Header Registration" and request a new header.
3. Enter your six-character sender name — for example, LGICOM. The name must represent your brand and cannot be generic (headers like "PROMOT" or "OFFERS" are no longer accepted).
4. Select the category this header will be used for — Transactional, Promotional, Service Implicit or Service Explicit. Transactional headers are alphabetic; promotional headers can be numeric.
5. Submit. Header approval typically takes 1 to 2 working days. Header registration is free on most portals.

You can register multiple headers under one entity — one for OTPs, another for marketing campaigns, another for appointment reminders.

Step 3 — Register your message templates

1. Go to "Content Template Registration" in your DLT portal.
2. Select the header this template belongs to.
3. Enter the template text with variables in {#var#} format. For example:

4. Select the message category (must match the header's category).
5. Submit. Template approval takes 1 to 7 working days, depending on the portal and volume of submissions.

Each variation of a message needs its own template. If you have a Hindi version and an English version of the same reminder, that is two templates.

SMS categories under TRAI

Every commercial SMS falls into one of four categories. The category determines when it can be sent, whether it reaches DND-registered numbers, and what consent is required.

There is also a Government category — exempt from all restrictions — but it is reserved for government departments and not available to businesses.

Template rules — what gets approved and what doesn't

Templates are where most registrations slow down. The DLT portal checks format, not just content.

Rules that must be followed

• Variable syntax: Every dynamic field must use {#var#} — not {{1}}, not [name], not %s. Using the wrong format causes immediate rejection.
• No variable at the start: Some operators reject templates that begin with a variable. Start with fixed text.
• No back-to-back variables: Placing two {#var#} tokens next to each other without fixed text between them is often rejected.
• Category must match the header: A promotional message sent through a transactional header will be scrubbed and dropped.
• URLs must be whitelisted: If your template contains a link, the full domain must be pre-registered. Shortened URLs (bit.ly, tinyurl) are rejected.
• Character-by-character matching: When you send an SMS, the operator compares the message against your approved template character by character. If the sent text differs — even by an extra space, a missing full stop, or an added emoji — the message is silently dropped. It will not appear as "failed" in your SMS provider dashboard; it will simply never arrive.

Template example — correct

Template example — will be rejected

Problems: starts with a variable, two variables back-to-back, all caps, excessive punctuation.

What it costs

After the one-time entity fee, you only pay for messages sent. There are no recurring DLT platform fees.

Timelines

Mismatches in your GST name vs PAN name, incomplete signatory letters, or wrongly formatted templates will add days. Get documents right before you start.

Common mistakes that delay or break registration

1. Wrong variable format. Using {{name}} or [otp] instead of {#var#}. This is the single most common template rejection.
2. GST name doesn't match PAN name. The entity name on your GST certificate must match your PAN exactly. A mismatch sends you back to document correction.
3. Generic sender IDs. Headers like "OFFERS" or "PROMOT" are no longer accepted. Use your actual brand name.
4. Promotional message on a transactional header. The operator scrubs the message, detects the mismatch, and drops it. You don't get a failure notification — the message simply vanishes.
5. Template text drift. You register "Dear {#var#}, your order {#var#} has shipped." but your application sends "Dear {#var#}, your order {#var#} has been shipped." — the extra "been" causes a scrubbing failure. The sent text must match character by character.
6. Shortened URLs. bit.ly, tinyurl.com, and other shorteners fail silently. Use your full branded domain and whitelist it.
7. Sending promotional SMS outside 10 AM – 9 PM. The message is blocked at the network level, not queued for later. You still get charged by your SMS provider.
8. Sending to DND numbers without DCA consent. Promotional messages to DND-registered numbers are silently dropped unless you have verified DCA (Digital Consent Acquisition) opt-in — which requires an OTP confirmation from the subscriber.

After registration — connecting to your SMS provider

Once your entity, headers and templates are approved on the DLT portal, you connect them to your SMS service provider. In LigiComms, this means:

1. Go to Settings → SMS and enter your provider credentials (Fast2SMS or Plivo). Credentials are encrypted at rest.
2. On the Templates page, add your DLT entity ID, sender headers and template IDs. The DLT wizard walks you through it if your provider is India-focused.
3. Pick a template, fill in the variables, select recipients, and send. Each SMS deducts from your credit wallet — the exact cost per segment is shown on the Rates page.

If a message fails to deliver — wrong number, network issue, DLT scrubbing rejection — the credit is automatically refunded to your wallet. You can see every send, delivery and refund in the SMS send log.

For detailed setup instructions, see the DLT-Ready SMS feature page.

Penalties for non-compliance

TRAI enforces DLT compliance through a progressive penalty structure:

Separately, under India's Digital Personal Data Protection Act (DPDP Act), processing personal data (including phone numbers) without valid consent carries penalties of up to ₹50 crore, and data breaches up to ₹250 crore.

DLT registration is not optional and not something to defer. The cost is negligible (₹5,900 once), the timeline is reasonable (under two weeks), and the alternative is having every commercial SMS you send blocked.

Frequently asked questions