Guides to business messaging in India.

DLT registration, step by step

Every business that sends SMS to Indian numbers must register on a DLT (Distributed Ledger Technology) platform run by the telecom operators, under TRAI's rules. Registration on one operator's platform is shared with the others.

1. Register your entity. Sign up as a Principal Entity on an operator DLT portal with your PAN, GST certificate or incorporation document, and a letter of authorisation. You receive a PE ID.
2. Register headers (sender IDs). Transactional and service headers are 6 letters (for example SPKNOW). Promotional headers are 6 digits. Recent TRAI rules also show a suffix after the header that tells customers the message type, such as -S for service, -T for transactional and -P for promotional.
3. Register content templates. Submit the exact wording of each message, with {#var#} where details change. Choose the right category: promotional, transactional, service implicit or service explicit.
4. Whitelist links and numbers. URLs, app links and callback numbers used inside messages must be registered with your templates, or messages are blocked.
5. Add your telemarketer. Link SparkNow as your telemarketer on the DLT portal so we can send on your behalf.
6. Map in SparkNow. Add the template IDs to your SparkNow panel. Every send is matched automatically.

Approval usually takes from a few hours to a couple of working days. Our team helps every customer through it.

Promotional, transactional and service SMS

Promotional messages may only be sent during the hours TRAI permits and never to customers who have blocked that category. SparkNow holds such messages automatically.

SMS length and Indian languages

• An English (GSM) SMS holds up to 160 characters. Longer messages are split into parts of 153 characters each.
• A Unicode SMS, needed for Telugu, Hindi and other Indian scripts or emoji, holds 70 characters, or 67 per part when split.
• One special character such as a curly quote can turn a whole message into Unicode. The SparkNow editor warns you and counts parts as you type.
• Each part is charged as one SMS, so short, clear messages cost less.

WhatsApp Business API essentials

• Opt-in first. Only message customers who agreed to hear from you on WhatsApp, and record when and how they agreed.
• Templates start conversations. Messages you send first must use a Meta-approved template in one of three categories: marketing, utility or authentication.
• The 24-hour window. When a customer messages you, you can reply freely (without templates) for 24 hours from their last message.
• Pricing. Meta charges per template message, with rates that depend on the category and the customer's country. Replies within the 24-hour window are not charged by Meta.
• Quality rating. If many customers block or report your messages, your number's quality rating drops and sending limits can be reduced. Send relevant messages to people who expect them.
• Messaging limits. New numbers start with a daily limit on how many customers they can message, which rises as you send good-quality messages.

Writing templates that get approved

• Write the full message with real wording. Avoid templates that are only variables, like "{{1}}".
• Don't start or end a WhatsApp template with a variable, and don't place two variables next to each other.
• Pick the right category. Offers in a utility template will be rejected or re-categorised.
• Add sample values for every variable so reviewers understand the message.
• Include your brand name, keep it polite, and give a way to opt out of promotions.
• For SMS, use the exact DLT wording; even a changed space can cause a template mismatch.
• Browse the template library for examples you can adapt.

SMS vs WhatsApp vs RCS vs voice

Most businesses get the best results by combining them: WhatsApp or RCS first, with SMS as the fallback, and voice for people who don't read messages.

Getting started with RCS

• RCS messages arrive in the phone's default messages app, so customers don't install anything.
• You create an RCS agent with your brand name, logo, colours, description and contact details. It goes through brand verification before launch.
• Design rich cards and carousels with images, titles, descriptions and buttons, and get them approved.
• SparkNow checks each number. Phones that can't receive RCS get your SMS fallback, so you still reach everyone.

Voice calls and calling rules

• Promotional voice calls must respect customers' DND preferences and the calling hours TRAI permits, and must come from caller IDs approved for that purpose.
• Service and transactional calls, such as payment or delivery reminders, follow their own number series and rules.
• Keep recorded messages under 30 seconds, say who you are in the first sentence, and offer a clear keypress option.
• Record in the language your customers speak. A Telugu message often gets far more keypresses in Andhra Pradesh and Telangana than an English one.
• AI voice agents should introduce themselves as an AI assistant and transfer to a person on request.

Glossary

These guides summarise rules as we understand them for general information. Regulations change, so check the latest TRAI and Meta guidance or ask our team before you launch.