Send SMS that actually get delivered.
India's enterprise-grade SMS gateway with 2-sec OTP delivery, DLT compliance built-in, and transparent pay-as-you-go pricing. No contracts. No setup fees.
Everything you need to communicate at scale
From one-time OTPs to mass marketing campaigns — one API, one dashboard, every use case covered.
Bulk SMS
Reach millions with a single API call. Intelligent routing, real-time DLR, and time-zone aware scheduling.
Explore Bulk SMSTransactional SMS
Priority-routed alerts, order updates, and account notifications. Delivered on all DND numbers, 24×7.
Explore TransactionalOTP Service
Sub-3-second one-time passwords with auto-retry, hash verification, and multi-channel fallback (SMS → Voice → WhatsApp).
Explore OTPPromotional SMS
TRAI-compliant promotional campaigns with audience segmentation, A/B testing, and click-to-action short URLs.
Explore PromotionalSMS API
RESTful API with SDKs for PHP, Python, Node.js, and Java. Webhooks, delivery callbacks, and sandbox testing.
View API DocsWhatsApp Business
Official WhatsApp Business API. Rich media templates, interactive buttons, and catalog messages for commerce.
Explore WhatsAppBuilt for businesses that can't afford dropped messages
We don't just forward SMS. We run our own carrier-grade infrastructure across multiple telecom operators — so your messages get through, every time.
Learn about usDirect Operator Connectivity
No third-party aggregators. We maintain direct SMPP connections with Airtel, Jio, Vi, and BSNL for the lowest latency and highest throughput.
DLT Registration Done For You
We handle your entire DLT registration — entity, sender ID, and template approvals — so you can start sending within 24 hours.
Real-Time Analytics Dashboard
Track delivery rates, operator-wise breakdowns, and campaign performance in real-time. Export reports in CSV, PDF, or via webhook.
Intelligent Failover Routing
If one route fails, your message automatically re-routes through backup operators within milliseconds. Zero manual intervention.
Pay What You Use
No monthly minimums, no expiry on credits. Your unused balance carries forward forever. Volume discounts kick in automatically.
Ship SMS in 5 minutes, not 5 days
Simple, RESTful API. No WSDL nightmares. No XML configs. Just a clean HTTP POST and your message is on its way.
- REST API with JSON request/response
- SDKs for PHP, Python, Node.js, and Java
- Delivery webhooks in real-time
- Sandbox environment for testing
- Comprehensive API documentation
Don't take our word for it
Here's what engineering and marketing leaders say about switching to OnlineSMSService.
"We switched to OnlineSMSService for OTP delivery and saw an immediate 15% increase in verification success rates. The latency dropped from 8 seconds to under 2. That directly impacted our conversion funnel."
"The DLT registration was the part we dreaded most. Their team handled the entire process end-to-end — entity registration, sender IDs, templates — and we were live in 48 hours. Incredible support."
"We push 100k+ notifications daily through their API. Six months in, zero downtime. The failover routing is genuinely seamless — we've never had to manually intervene on a failed delivery."
Ready to start sending?
Get 10,000 free SMS credits. No credit card required. Set up in under 5 minutes.