OTP SMS Service Provider for Logins, Payments and Sign-ups

Why OTP delivery speed matters

A user typing a login or checkout OTP will wait a few seconds, rarely a full minute. If the code is late, they tap resend, get a second code that confuses them and often abandon the cart or the sign-up. Every delay shows up in your conversion numbers and your support tickets.

OTP traffic on our platform goes through direct connectivity to Jio, Airtel, Vi and BSNL, with 6+ redundant routes for backup. Most OTPs are typically delivered in a few seconds, and the delivery report tells you exactly what happened to each one.

Choosing an OTP SMS service provider

Our platform handles up to about 10,000 SMS per second, so a login spike at 9am or a festive sale at midnight does not create a backlog. Use this checklist when you compare vendors:

• Direct operator routes instead of long reseller chains
• Delivery report webhooks, so your app can offer a fallback
• Enough throughput for sale launches or exam results
• Help writing a template that passes DLT review
• Support you can reach when users report missing OTPs

Integrating the OTP API

Your server generates the code, stores it with an expiry and calls our HTTPS API with the mobile number, the DLT template ID and the code as a variable. The delivery status then posts to your webhook. Keep expiry short, around 5 to 10 minutes, and limit resend attempts per number.

For a fallback, many teams pair SMS OTP with a WhatsApp authentication message. Our WhatsApp Business API charges ₹0.16, ₹0.14 or ₹0.12 per authentication message depending on the plan, charged on Meta-confirmed delivery.

OTP security and fraud controls

OTPs protect accounts only when the system around them is sound. Generate codes with a secure random function, store only a hash and let each code work once. Lock the flow after a few wrong attempts, and slow down repeated requests from the same number or IP address.

SMS pumping, where bots trigger large numbers of OTP requests to inflate traffic, is a real cost risk for apps. Limit OTP requests per number per hour, add a captcha on public sign-up forms and watch your delivery reports for sudden spikes from unusual number ranges.

Never put the OTP inside a URL or a promotional message, and remind users in the template not to share the code with anyone, including people who claim to be from your company.

Writing an OTP template that gets approved

Keep it short: the code, what it is for, how long it is valid and a warning not to share it. Put the code at the start so it shows in the notification preview without opening the app. Leave out offers and links. Register the template under the transactional or service category with your -T or -S header, and keep the code inside one {#var#} field.

OTP pricing follows our standard list: ₹0.20 per SMS on Starter, ₹0.15 on Business and custom Enterprise rates, plus 18% GST, billed only on delivery.