WhatsApp Business Calling API
Make and receive voice calls directly over WhatsApp, on your existing number, inside ChatWerk, without switching tools.
Overview
The WhatsApp Business Calling API enables your business to handle voice calls within the same WhatsApp channel used for chat. Incoming calls arrive in the ChatWerk Inbox alongside regular messages. Your team picks up without leaving the platform — full conversation history visible, no context lost, no handoff required.
This is particularly useful for support teams dealing with complex issues that are easier to resolve over voice, or for businesses that already rely on WhatsApp as their primary customer channel.
Availability: WhatsApp Calling is a paid add-on. Contact ChatWerk Support to enable it on your account.
Call types
Inbound calls
Customers initiate a call directly from the WhatsApp chat interface. The call appears in ChatWerk and is answered by your team there. Inbound calls are free of charge for your business.
Outbound calls
Your business can initiate calls to customers, subject to prior customer consent. Before placing an outbound call, a Call Permission Request (CPR) must be sent and accepted by the customer. The CPR is delivered as a standard template message and billed accordingly.
Outbound call duration is billed in 6-second increments, always rounded up. Rates are country-specific. A 70-second call, for example, is billed as 12 increments.
Current rates are available on the Meta Rate Card.
| Call type | Who initiates | Cost |
|---|---|---|
| Inbound call | Customer | Free |
| Outbound call | Your business | Per 6-second increment, country rate applies |
| Call Permission Request (CPR) | Your business | Standard template message price |
Service window behavior
Calls interact with the 24-hour customer service window in the same way incoming messages do:
- A customer calls your number (answered or missed) → service window opens
- A customer answers your outbound call → service window opens
- Outgoing free-form messages can be sent in parallel during an active call (standard messaging rates apply)
This means a missed inbound call is sufficient to open the window and allow free-form follow-up messages.
Prerequisites
- An active WhatsApp Business API number connected to ChatWerk
- A minimum messaging limit of 1,000 business-initiated conversations on the number
- SIP/WebRTC infrastructure experience (required for outbound calls) WhatsApp Calling add-on enabled on your ChatWerk account
Limitations
- Voice calls only — video calls are not yet supported by the WhatsApp Business Calling API
Updated about 2 months ago