OTP and verification
OTP SMS Service for Logins and Payments
Verify users in seconds. Send one-time passwords over SMS on a transactional route, with WhatsApp and voice as backup when a message is slow.
- Transactional route, sent at any hour
- Fallback to WhatsApp or a voice OTP
- Simple API your developers can add in a day
- Delivery and verification reports
Office in Sector 115, Mohali · +91 70180 62319
- DLT registeredCommercial SMS in India
Meta WhatsAppBusiness Partner
30-minute call, Mon to Fri
Book a demo
OTP and verification
What is an OTP SMS service?
An OTP SMS service sends a short, single-use code to a user's phone to prove they own the number. Apps use it for sign-ups, logins, password resets, payments and order confirmations.
An OTP is only useful if it arrives fast. We send OTPs as DLT registered service messages, so they are not blocked by DND settings or time windows, and you can add a WhatsApp authentication message or a voice call as a fallback for users who do not get the SMS.
482913 is your OTP to log in to Zenspire. It is valid for 10 minutes. Do not share it with anyone.
What you get with otp & verification sms
-
Priority transactional delivery
OTPs go out as service messages on your brand header, around the clock, without DND or time-window limits.
-
WhatsApp and voice fallback
If an SMS is not delivered in time, send the code as a WhatsApp authentication message or read it out in a voice call.
-
OTP generation and checking
Let us create and verify codes with expiry and retry limits, or send codes your own system generates.
-
Templates ready for approval
We draft OTP templates that pass DLT approval, with your brand name and a clear do-not-share line.
-
Fraud and abuse limits
Rate limits per number and per IP help stop bots from running up your bill with fake sign-ups.
-
Delivery and conversion reports
Track how many OTPs were delivered and how many were entered, by network and by hour.
How businesses use otp & verification sms
Common ways our clients put otp & verification sms to work.
Apps and SaaS
Sign-up and login verification, password resets and new device checks.
Fintech and banking
Payment confirmation, account changes and high-risk action approvals.
E-commerce
Cash on delivery confirmation and account login at checkout.
Gaming and fantasy sports
Account verification and withdrawal confirmations at peak match times.
Healthcare
Patient portal logins and report access.
Education
Student and parent portal logins and exam registrations.
See otp & verification sms working for a business like yours.
How to get started
From the first call to your first campaign.
- 01
Book a demo
We look at your sign-up flow, expected OTP volume and peak hours.
- 02
Register templates
We register your service header and OTP templates on DLT.
- 03
Integrate the API
Your developers add one API call to send and one to verify. We share sample code and test numbers.
- 04
Go live and monitor
Watch delivery and verification rates, and switch on fallback channels where they help.
Compliance
Built for Indian OTP rules
OTPs are service messages under TRAI rules, which lets them reach every user at any time, as long as the setup is right.
- OTP templates registered as service (implicit) messages on DLT
- Your brand name in the header and in the message text
- Clear do-not-share wording to protect your users
- No promotional content mixed into OTP messages
API and integrations
One API for every channel
Send and verify OTPs over SMS, WhatsApp or voice through the same API, so you can change the fallback order without new code.
- Send and verify endpoints with expiry and retry settings
- Webhooks for delivery and verification events
- Test mode and sample code for your developers
- Per-country and per-network delivery reports
- DLT registeredCommercial SMS in India
- Meta WhatsAppBusiness Partner
More from the CPaaS platform
Every channel runs from the same dashboard and API.
-
Bulk SMS
Reach every mobile phone in India, smartphone or not. Send offers, alerts and reminders from a DLT registered platform, by dashboard or API.
-
WhatsApp Business API
Message customers where they already are. Send offers, alerts and support replies on WhatsApp at scale, from one number your whole team can use.
-
Voice: IVR, Calls & Missed Call
Handle every call with a cloud IVR, reach customers with recorded voice calls and collect leads with a missed call number. No phone hardware to buy.
-
Email API & SMTP
Send receipts, password resets, invoices and newsletters from your app or website, with the domain setup and tracking that keep them out of spam.
FAQs
Questions about otp & verification sms
Still unsure? Call +91 70180 62319 or message us on WhatsApp.
How fast is OTP SMS delivery?
On a transactional route most OTPs arrive within a few seconds. Delivery speed can vary by network and handset, which is why we offer WhatsApp and voice OTP as fallbacks for users who do not receive the SMS.
Can OTPs be sent to numbers on DND?
Yes. OTPs are service messages, so they reach numbers registered on DND and can be sent at any hour, as long as your header and template are registered for that purpose on DLT.
What is a WhatsApp OTP?
WhatsApp OTP uses Meta's authentication message templates to deliver a code inside WhatsApp, often with a copy-code button. As a Meta WhatsApp Business Partner we can set this up on your WhatsApp Business API number as a primary channel or a fallback.
Do you generate the OTP or do we?
Either works. Our API can create and verify codes with expiry and retry limits, or you can generate codes in your own system and use us only to deliver them.
How do we stop fake sign-ups using our OTPs?
We set rate limits per number, per IP and per time window, and can block number ranges showing abuse. This protects your budget from OTP pumping attacks.
How is OTP SMS priced?
Pricing depends on monthly volume and which fallback channels you use. Book a demo and we will share a written quote.
Book a demo
See otp & verification sms in a live demo
Pick a 30-minute slot. We show the platform, answer your questions and send a written quote after the call.