Alert21

Alert21 is ranked #12 of 67 in transactional SMS software on Freedom251. It runs on Web.

Alert21 plans and pricing

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SMS pay-as-you-go Not published Usage-based billing · Volume discounts as sending scale grows · Prepaid balance in Indian Rupees alert21.in · 24 Sept 2026

Compared on transactional SMS software

Pay-as-you-go: Yes
SMS API: Yes
Delivery status: Yes
Webhooks: Yes

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