OTP Flow

Send SMS in India without DLT registration

DLT registration (entity, header and template approval) can take days and gets in the way of shipping. With OTP Flow you skip it: your OTPs go out through our already-approved DLT template and sender ID, so you can start sending within minutes of signing up.

Start for free API docs

From ₹0.40 per OTP · No DLT registration · No KYC

POST /send-otp
curl -X POST https://otpflow.in/send-otp \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{ "number": "9876543210",
        "purpose": "login",
        "ttl": 10 }'

# → { "success": true, "otp_id": "otp_k3J9xQ2mP0aZ7Vb1" }

curl -X POST https://otpflow.in/verify-otp \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{ "otp_id": "otp_k3J9xQ2mP0aZ7Vb1", "otp": "123456" }'

How it works without your own DLT

Every SMS in India must travel over a registered DLT route. We have already registered the entity, sender ID and OTP template, so your requests simply reuse them. You send the number, the purpose and the OTP; we fill the approved template and deliver.

  • No entity, header or template registration on your side
  • One API call: POST /send-otp
  • Delivered through DLT-registered routes
  • Start sending the same day you sign up

What you can send

The approved template covers OTP messages that include the code, your purpose and the validity. That makes it ideal for login, signup, payment confirmation, password reset and delivery verification.

Get started in three steps

Sign in with Google or email, add funds with UPI, cards or crypto, create an API key and call /send-otp. Verification is a second call to /verify-otp using the returned otp_id.

Good to know

OTP Flow is built for transactional one-time passwords (login, signup, payments, delivery and similar verification). Promotional or bulk marketing messages are not supported.

Frequently asked questions

Do I need my own DLT entity or template?+

No. OTPs are sent using our pre-approved DLT entity, sender ID and OTP template, so you don't have to register anything yourself.

Can I change the SMS text?+

The wording follows the approved template. You control the OTP value, the purpose label and the validity time.

Is delivery as fast as with my own DLT?+

Messages use the same DLT-registered routes and are typically delivered within seconds.

Send your first OTP today

Create an account in under a minute. No DLT registration, no KYC, no subscription.

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