Question
Is it technically possible to receive a PSTN call, convert it to VoIP, and then forward it to the WhatsApp Calling API using Twilio?
Product
Programmable Voice
Answer
No, it is not currently possible to forward a PSTN or VoIP call to WhatsApp Calling via Twilio.
Details
-
WhatsApp Calling API Limitations:
The WhatsApp Calling API is designed for initiating outbound calls from your application to WhatsApp users. It does not support receiving or bridging inbound PSTN or VoIP calls to WhatsApp. -
No Direct Bridging:
Twilio does not provide a mechanism to directly connect or bridge an inbound PSTN or VoIP call to a WhatsApp user via the WhatsApp Calling API. -
Intended Use Case:
WhatsApp Business Calling is intended for outbound calls only (from your application to a WhatsApp user). Inbound call flows from PSTN/VoIP to WhatsApp are not supported.
Alternative Approaches
If you need to connect users across different channels (e.g., PSTN to WhatsApp), you may need to design a custom application to manage call logic and user experience. However, direct bridging through Twilio’s APIs is not supported at this time.
Additional Information
Summary Table
| Scenario | Supported by Twilio? |
|---|---|
| Outbound call from app to WhatsApp user | Yes |
| Inbound PSTN/VoIP call to WhatsApp user | No |
| Bridging PSTN/VoIP to WhatsApp via API | No |
If you have a specific use case or workflow in mind, please provide more details so we can help explore possible solutions or workarounds.