Alert21 review
A pay-as-you-go SMS API for OTPs, service alerts and delivery tracking.
Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026
Alert21 is a cloud-based SMS service from Scriza Private Limited, delivered through a web interface and REST API. It is designed for businesses sending transactional and service messages in India, including OTPs, operational alerts and lifecycle receipts. Small, mid-market and enterprise teams can use approved DLT templates, sender details and Principal Entity mappings to submit messages. Unicode and regional-language SMS extend its use to localized communication.
The API’s operational controls are a notable strength for application teams. Delivery receipts use normalized lifecycle states, while signed HTTP webhooks can report message events to connected systems. Idempotency, rate limits, request IDs, usage logs and reporting help teams manage requests and follow message outcomes. Bulk and scheduled sending cover campaigns and timed notifications, alongside transactional traffic. These capabilities make Alert21 a fit for teams that want SMS integrated into application workflows rather than a standalone messaging tool.
Pricing is pay-as-you-go with a prepaid balance in Indian Rupees, and volume discounts apply as sending scales. According to the published pricing details, rates depend on destination, route, encoding, segment count, volume and taxes, so teams should account for those variables when estimating spend. Support channels include email, phone and documentation; support is not available 24/7. The stated compliance credential is ISO 27001. Choose Alert21 if DLT-aware OTP and service messaging, delivery tracking and API controls match your needs. Teams that require confirmed two-way messaging or a predictable monthly quota should compare alternatives before committing.
Alert21 pros and cons
- Where it wins
- Maps DLT templates, sender IDs and Principal Entities
- Reports delivery lifecycle states through receipts and signed webhooks
- Supports Unicode, regional-language, bulk and scheduled SMS
- Where it doesn't
- No monthly message quota is stated
- SMS rates vary by destination, route, encoding, segments, volume and taxes
- Two-way messaging is not specified
Alert21 fact sheet, pricing and score →
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