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Power your campaigns with bulk SMS services, promotional SMS, transactional SMS, and OTP SMS delivery. Duotech Solutions delivers DLT-compliant messaging with instant API integration.
Bulk SMS lets you send the same message to thousands of customers at once. It's the quickest way to share offers, send order updates, remind customers about payments, or deliver OTPs. As a trusted bulk SMS provider in India, Duotech Solutions delivers your messages across every telecom operator in the country with 99.9% uptime.
Every message is fully TRAI and DLT compliant, so your campaigns run without interruptions or rejections. Pricing starts at just โน0.15 per SMS with flexible plans for every budget. Send campaigns from our easy-to-use dashboard or connect your own software using our simple REST API โ getting started takes minutes, not weeks.
| Dimension | Promotional Routing | Transactional Routing |
|---|---|---|
| Use Case | Marketing, offers, discounts, and brand announcements. | Order confirmations, payment alerts, OTPs, and account updates. |
| Time Horizon | 9:00 AM โ 9:00 PM | 24 hours a day |
| DLT Mandate | Required by law | Required by law |
| Identifier Prefix | Sender ID must start with 'D' | Standard 6-character sender ID |
| Performance Limit | Up to 10,000 messages / minute | Up to 100,000 messages / minute (priority) |
| Optimized For | Offers, events, and customer retention. | OTPs, payment alerts, and login verifications. |
| Sender ID Layout | 6-character alpha format (e.g., DUOTCH) | 6-character alpha format (e.g., DUOTCH) |
| Template Rule | Must be pre-approved on DLT | Must be pre-approved on DLT |
Need to verify a login or a payment in seconds? Our OTP messages go out on a priority route and reach your customer in under 2 seconds โ fast enough to keep the flow smooth and secure. Built for high-security use cases like banking, logins, and payments.
Send SMS in Hindi, Tamil, Telugu, and other regional languages without the text getting garbled.
Add each customer's name, order number, or any other detail automatically in every message.
Import contacts from Excel or CSV files โ we detect and validate the phone number column for you.
Add SMS to your own app or website easily with our REST API and ready-made SDKs.
Pick any future date and time and we'll send your campaign automatically โ no manual work.
Set up recurring reminders for payments, renewals, and updates โ and forget about them.
Tag and filter your contacts so you can target the right audience for every campaign.
See exactly which messages were delivered, failed, or are still pending โ down to each number.
Send bank-grade OTPs automatically, with priority delivery for time-sensitive codes.
Let customers reply to your messages and receive their responses in real time.
Shorten links in your messages and track how many people actually clicked them.
Use your own 6-character sender ID (like DUOTCH) so customers always see your brand.
Manage campaigns, credits, and delivery reports from one clean, easy-to-use dashboard.
Give each team member their own login with restricted access, so only the right people can send.
Start faster with a library of pre-approved SMS templates for common use cases.
Download your delivery logs in CSV or PDF for audits, records, and compliance.
Everything you need to know about DLT registration, why it's mandatory for business SMS in India, and how we handle it for you.
DLT (Distributed Ledger Technology) is a compliance platform set up by TRAI (Telecom Regulatory Authority of India) to regulate commercial SMS. Every business sending promotional or transactional messages in India must register on DLT and get approval for their sender IDs and message templates before sending.
In simple terms: you register your business, pick a 6-character sender ID (like DUOTCH), and get your message templates approved. Once that's done, your messages are good to go. Messages from unregistered businesses are simply blocked by the telecom operators.
Sign up on your telecom operator's DLT portal (Jio, Airtel, Vodafone, BSNL) with PAN, GST, and business identity documents.
Receive your Principal Entity ID after verification. This usually takes 1โ2 business days.
Register a 6-character alphabetic sender ID (e.g., DUOTCH) linked to your brand.
Write your SMS templates for promotional, transactional, or service categories and submit for DLT approval.
Link your PE ID, sender ID, and templates to your Duotech account so you can start sending SMS right away.
DLT registration typically takes 2โ5 business days. We handle the entire process for you โ just submit your documents and we'll take care of the rest.
DLT registration can be confusing, so our team does the heavy lifting. Just share your documents and we'll complete the registration and approvals on your behalf.
Get DLT HelpNew to DLT? Read the step-by-step DLT registration guide
Integrate transactional notifications seamlessly using our simple, robust REST architecture. Deliver targeted alerts globally via concise JSON schemas.
{
"api_key": "your_api_key_here",
"sender_id": "DUOTCH",
"phone": "91XXXXXXXXXX",
"message": "Hello {name}, your code is {otp}.",
"template_id": 12345
}
Get instant delivery status callbacks to your server as messages are processed.
Predictable endpoints utilizing declarative standard HTTP calls and protective rate barriers.
Full support parsing structural JSON payloads and historic XML formats depending on preferences.
Pre-packaged wrappers for deployment across Python, Node, PHP, Java, and common backend frameworks.
Deploy production code environments via drop-in language modules
<?php $data = [ 'api_key' => 'YOUR_API_KEY', 'sender_id' => 'DUOTCH', 'phone' => '91XXXXXXXXXX', 'message' => 'Your verification code is 847291', 'template_id' => 12345 ]; $ch = curl_init('https://api.duotechsolutions.in/v1/send'); curl_setopt($ch, CURLOPT_POST, true); curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($data)); curl_setopt($ch, CURLOPT_HTTPHEADER, ['Content-Type: application/json']); curl_setopt($ch, CURLOPT_RETURNTRANSFER, true); $response = curl_exec($ch); curl_close($ch);
const axios = require('axios'); const sendSMS = async () => { const response = await axios.post('https://api.duotechsolutions.in/v1/send', { api_key: 'YOUR_API_KEY', sender_id: 'DUOTCH', phone: '91XXXXXXXXXX', message: 'Your verification code is 847291', template_id: 12345 }); };
import requests payload = { "api_key": "YOUR_API_KEY", "sender_id": "DUOTCH", "phone": "91XXXXXXXXXX", "message": "Your verification code is 847291", "template_id": 12345 } response = requests.post( "https://api.duotechsolutions.in/v1/send", json=payload, headers={"Content-Type": "application/json"} )
import java.net.http.*; import java.net.URI; var client = HttpClient.newHttpClient(); var json = "{\"api_key\":\"YOUR_API_KEY\",\"sender_id\":\"DUOTCH\",\"phone\":\"91XXXXXXXXXX\"}"; var request = HttpRequest.newBuilder() .uri(URI.create("https://api.duotechsolutions.in/v1/send")) .header("Content-Type", "application/json") .POST(HttpRequest.BodyPublishers.ofString(json)) .build();
use Illuminate\Support\Facades\Http; $response = Http::withHeaders([ 'Content-Type' => 'application/json' ])->post('https://api.duotechsolutions.in/v1/send', [ 'api_key' => config('sms.api_key'), 'sender_id' => 'DUOTCH', 'phone' => '91XXXXXXXXXX', 'message' => 'Your verification code is 847291', 'template_id' => 12345 ]);
Provision an immediate testing environment with 100 sandbox units. Zero initial commitments required.
Track every SMS payload with precision. Gain total engineering visibility into your scale, transmission logs, and immediate delivery verification parameters.
Monitor transaction streams as they process. Observe latency status shifts within milliseconds of execution, backed by granular error diagnostics.
Evaluate aggregate data distributions cleanly. Graph core indicators across user segments, trend thresholds, and historical delivery benchmarks.
Extract native delivery registers in formatted CSV or high-fidelity PDF layouts. Perfect for internal audits, telemetry alignment, and compliance reporting.
Isolate payload click-through rates along explicit route redirects. Attribute business conversion values back down to precise messaging segments.
Feed automated transmission updates seamlessly into your microservices via concurrent asynchronous HTTP POST notifications.
Algorithmic models evaluate platform traffic distributions to continuously compute superior delivery execution windows and bypass potential congestion nodes.
Configured programmatic distribution channels constructed explicitly to optimize user interaction flows across specialized target industries.
Transparent payload metrics tiering clear of unexpected baseline provisions. Select an allocation volume engineered around your existing operational scope.
Engineered for localized early deployment, small workflows, and simple audience campaign tests.
Optimized for growing applications requiring direct API loops and immediate telemetry webhooks.
Tailored explicitly for high-throughput scaling frameworks requiring custom service SLAs.
Deliver bulk messages to international destinations seamlessly. Reach subscribers worldwide via low-latency carrier connections engineered for high deliverability parameters.
Review comprehensive tariff tables and specialized routing access regulations globally.
Dedicated bulk SMS landing pages for India's top business hubs. Same platform, same โน0.15/SMS pricing, and full DLT support in every city.
Seamlessly connect your favourite platforms and tools with our SMS gateway. Pre-built integrations, powerful APIs, and SDKs for every major framework.
Real businesses rely on Duotech for fast, reliable SMS every day. Here's what a few of our customers have to say.
"We use Duotech to send appointment reminders to our patients automatically. It's cut our no-show rate by 35% โ the clinic runs far more smoothly now."
"Their API was easy to integrate into our app for OTP verification. It's been rock solid โ we haven't had a single downtime issue in nine months."
"Sending offers to our store customers used to be a real hassle. Now we just upload our Excel list and schedule the campaign โ it goes out to every store without any manual work."
"Order updates and delivery alerts now reach our customers instantly. Since we switched, calls asking 'where's my order?' have dropped by 40%."
"Keeping parents informed used to take forever. Now we send exam alerts and updates in Hindi and English, and every message reaches parents without a hitch."
Everything you need to know about our Bulk SMS service. Can't find your answer? Contact us.
Join 500+ businesses using Duotech Bulk SMS to reach millions of customers. Get started with a free trial today.