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Delivery channel

Telegram OTP API for websites and apps

Use Telegram to verify phone numbers during signup, login, account recovery, and sensitive product actions.

Quick Answer

Cascade Telegram OTP API is a server-side way to send one-time codes through Telegram. Successful delivery costs 3 credits, a code expires after 5 minutes, and integration uses POST /api/otp/send and POST /api/otp/verify.

Summary

Cascade sends a six-digit code through Telegram after a backend request and verifies the value entered by the user.

Key Takeaways

  • Telegram is publicly available in Cascade.
  • Successful delivery costs 3 credits.
  • WhatsApp uses the same API integration.
  • New accounts receive 1000 credits for testing.
  • SMS is not an active public fallback.

Why use Telegram OTP

Telegram OTP can fit products whose users already work with Telegram and accept service messages there. The same channel can support signup, login, recovery, and confirmation of a specific action.

Cascade handles code creation, Telegram delivery, five-minute expiration, server-side verification, API responses, and operation history in the company dashboard.

This is outbound delivery to your own users. Cascade does not rent temporary numbers or receive third-party verification codes.

Product use cases

Product Example
SaaS Login, employee invitation, or recovery
E-commerce Customer or important order-change confirmation
Fintech Additional confirmation based on transaction risk
CRM Customer or employee phone verification
Mobile app Phone-based signup and login
Internal tool Confirmation of an administrative action

OTP does not replace a complete security model. Add session validation, limits, anti-fraud controls, and another factor where risk requires it.

One API integration

Telegram uses the common Cascade endpoint with an explicit channel:

curl -X POST "https://cascade.kz/api/otp/send" \
  -H "Authorization: Bearer $CASCADE_API_TOKEN" \
  -H "Content-Type: application/json" \
  -H "Accept: application/json" \
  -d '{"phone":"77001234567","purpose":"signup","channel":"telegram"}'

After the user enters a code, the backend calls:

curl -X POST "https://cascade.kz/api/otp/verify" \
  -H "Authorization: Bearer $CASCADE_API_TOKEN" \
  -H "Content-Type: application/json" \
  -H "Accept: application/json" \
  -d '{"phone":"77001234567","code":"482910","purpose":"signup"}'

Phone and purpose must match the send request. Complete the user action only after success: true.

Pricing and pilot metrics

Successful Telegram delivery costs 3 credits with no subscription fee. A new account receives 1000 starting credits for integration testing.

Measure successful delivery, time to code entry, verification success, resend volume, unavailable-channel errors, and credits per verified user. Request volume alone does not show business value; completed signup or login does.

Telegram and WhatsApp together

Both channels have the same Cascade cost and use one backend integration. Enable them according to company settings and audience availability.

Do not claim that one messenger always performs better. Pilot both with your own users and compare delivery, verification, and resend data. See the full channel comparison.

Limitations

  • Telegram must be accessible to the recipient.
  • An external channel can delay or fail a message.
  • The Bearer token belongs on the server only.
  • Send and verify require independent rate limits.
  • Resend needs a cooldown.
  • The public SMS provider is not live, so SMS fallback must not be promised.

Launch a pilot

Create an account, store the API key in backend secrets, and test with consented numbers. Before real traffic, verify success, invalid code, expiration, resend, and UI handling for 422 and 429.

Start free · View pricing · Open documentation

FAQ

How much does Telegram OTP cost?
Successful Telegram OTP delivery costs 3 credits.
Can Telegram and WhatsApp share one API integration?
Yes. Cascade supports both channels in the same send and verify flow.
How long does a Telegram OTP remain valid?
A standard six-digit Cascade code is valid for 300 seconds, or 5 minutes.