Is the WhatsApp Business Calling API free?

Calls that customers start are free, according to Meta's calling pricing documentation. Calls that your business starts are charged, billed in six-second pulses at a rate that depends on the country code of the number you call and your monthly volume tier. You need a valid payment method on file to place calls.

Can a business call customers on WhatsApp without permission?

No. Before your business can call a WhatsApp user, that user must grant call permission. You can ask with an interactive call permission request inside the customer service window or with an approved template outside it, and the customer can also grant permission by calling you or from your business profile.

Which countries support WhatsApp business-initiated calls?

Customer-initiated calling is available wherever the Cloud API is available. Meta's documentation states that business-initiated calling is not available in the United States, Canada, Egypt, Vietnam and Nigeria, and your business phone number's country code must be on Meta's supported list.

Can an AI voice agent answer WhatsApp calls?

Yes, the Calling API delivers the call audio to your system, so a voice agent can answer it like any other call. In practice the agent should handle routine questions and hand the call to a person, with context, when the conversation needs one.

Does a WhatsApp call open the 24-hour messaging window?

Yes. Meta's pricing documentation says the customer service window starts or refreshes when a user calls your business, whether or not you accept the call, and when a user accepts a call from you. You can then follow up in the chat with free-form messages.

WhatsApp Business Calling API: Setup, Pricing and AI Voice Agents

The WhatsApp Business Calling API lets customers call you from the chat and lets you call customers who gave permission. Here is how it works, what it costs, the rules to follow and where AI voice agents fit.

MonoChat Team Updated: October 13, 2026 7 min read

On this page

What is the WhatsApp Business Calling API?
How WhatsApp calling works: inbound and outbound
Eligibility and requirements
WhatsApp Business Calling API pricing
Technical setup: WebRTC or SIP
AI voice agents on WhatsApp calls
How to run WhatsApp calls with MonoChat
Sources

The WhatsApp Business Calling API lets customers call your business with the call button in a WhatsApp chat, and lets your business call customers who have granted call permission, on the same number you use for messaging. Calls run over the internet (VoIP), and your system or contact center receives them through the API. Calls that customers start are free; calls your business starts are charged per six-second pulse by destination country.

For support and sales teams, this closes a gap. Until calling arrived, a chat that needed a conversation meant asking for a phone number and dialing out from a different line. Now the call happens in WhatsApp, next to the chat history. This guide covers how calling works, the permission rules, how Meta prices calls, technical setup, and how AI voice agents fit in.

What is the WhatsApp Business Calling API?

The Calling API is part of the WhatsApp Business Platform (Cloud API). Meta made it available in July 2025. It supports two directions:

User-initiated calls. A customer taps the call icon in your chat, or a call button you sent, and your team or voice agent answers.
Business-initiated calls. Your business calls a WhatsApp user who has given you permission to call.

Meta’s documentation describes voice calling today, with video and screen sharing still in development. Calls use the same business phone number and display name as your messages, so customers see a familiar business rather than an unknown caller.

How WhatsApp calling works: inbound and outbound

	Customer calls you	You call the customer
Permission needed	No	Yes, the customer must grant call permission
Cost (per Meta)	Free	Charged per six-second pulse
Where available	Wherever the Cloud API is available	Not in the US, Canada, Egypt, Vietnam or Nigeria
Typical uses	Support, sales questions, urgent issues	Callbacks, confirmations, follow-ups the customer agreed to
Effect on the chat	Opens or refreshes the 24-hour customer service window	Opens or refreshes the window if the customer accepts

Inbound calls

You can make calling visible in several ways:

The call icon in the chat. You control whether it is shown, including by country.
Call buttons in messages. A free-form voice call button inside the service window, or a voice call button on a template.
Call deep links. Links that open a WhatsApp call to your business, with an optional context string so you know which page or campaign the call came from.
Business calling hours. When you are closed, WhatsApp can steer customers to message you instead of calling, so fewer calls go unanswered.

Outbound calls and call permission

Business-initiated calls need the customer’s permission first. Meta gives you four ways to get it:

Free-form request inside an open customer service window: an interactive message of type call permission request.
Template request outside the window: an approved template with a call permission request component. Meta requires body text so the customer understands why you are asking.
Callback permission: if you turn on the callback setting, a customer who calls you grants temporary permission automatically.
Business profile: the customer can grant permission from your profile.

A granted permission is either temporary (7 days from approval) or permanent, and the customer can revoke it at any time. Meta also sets guardrails per business and customer pair:

At most 1 permission request in 24 hours and 2 in 7 days. These limits reset when a call connects.
After 2 consecutive unanswered calls, the customer gets a system message asking whether to keep the permission.
After 4 consecutive unanswered calls, the permission is revoked automatically.

A sample request that explains the reason:

Hi Omar, our technician can talk you through the router reset in about 5 minutes. Can we call you on WhatsApp today between 2 and 5 PM?

[Allow calls]  [Not now]

Asking at the moment a call is clearly useful gets a better answer than a blanket “May we call you?” sent to everyone. It also matches the spirit of WhatsApp opt-in: people should expect your contact.

Eligibility and requirements

Before you turn calling on, check these points from Meta’s calling documentation:

Cloud API. Calling is a Cloud API feature on the WhatsApp Business Platform, not part of the standalone Business app.
Messaging limit. Your business needs a daily messaging limit of at least 2,000 unique recipients to use calling.
Supported country code for your business phone number.
Business-initiated calling restrictions in the countries listed above.
A payment method on file before you place paid calls.
A calls webhook subscription so your system receives call events.

If you are still setting up the API, start with our guide on how to get the WhatsApp Business API.

WhatsApp Business Calling API pricing

Meta’s calling pricing works differently from messaging:

Customer-initiated calls are free.
Business-initiated calls are charged. Duration is billed in six-second pulses, and partial pulses round up. A 56-second call counts as 10 pulses.
Rates depend on the country code of the number you call and on a volume tier based on minutes called in the calendar month, using the same tier logic as messaging. If a call crosses into a cheaper tier, the whole call is priced at the lower rate.
Call permission request messages are billed under Meta’s normal per-message pricing.
Calls and messaging work together. A call from the customer, even one you do not answer, starts or refreshes the 24-hour customer service window, as does a customer accepting your call.

Meta publishes per-pulse calling rates in downloadable rate cards by currency, separate from the messaging rate card. Check the current card before you budget, and see our WhatsApp API pricing guide for the messaging side of the bill.

Technical setup: WebRTC or SIP

The Calling API gives you three ways to connect the audio:

Option	Signaling	Media	When it fits
Default	Graph API and webhooks over HTTPS	WebRTC	Browser-based agent apps and custom builds
SIP with WebRTC media	SIP over TLS	WebRTC	Teams with a SIP setup that can handle WebRTC media
SIP with SDES media	SIP over TLS	SRTP with SDES key exchange	Contact centers built on traditional SIP equipment

The SIP options require explicit enablement. Meta lists OPUS as the standard audio codec, with PCMA and PCMU also supported. If you are not building this yourself, a platform that already handles WhatsApp calls saves you the signaling and media work.

AI voice agents on WhatsApp calls

Because the call audio reaches your system, a voice agent can pick up before a person does. A sensible setup looks like this:

The AI answers and identifies the need. It greets the caller by name if the number is known and asks what they need.
It handles routine requests. Opening hours, order status, booking changes, simple troubleshooting, using your knowledge base and connected tools.
It hands over when it should. Complaints, payments, sensitive topics, or any caller who asks for a person go to a human, with a summary of what was said.
It leaves a record. A summary and outcome attached to the customer’s conversation, so the next agent does not ask the same questions.

Caller: Hi, I need to move my appointment to next week.
Voice agent: Of course. I have Tuesday at 11:00 or Wednesday at 3:30 PM. Which works for you?
Caller: Tuesday at 11.
Voice agent: Done. You will get a confirmation in this chat in a moment.

Be transparent that the caller is speaking with an automated assistant, keep sensitive decisions with people, and read our notes on the WhatsApp AI chatbot policy before you launch. Test the handover path as carefully as the happy path.

How to run WhatsApp calls with MonoChat

MonoChat puts WhatsApp calls next to your chats, so a call is one more part of the customer’s conversation rather than a separate system.

Connect and turn on calling. You connect your WhatsApp Business API number to MonoChat and turn on calling where it is available for your account. WhatsApp calls in MonoChat cover both inbound and outbound calls.
Route calls to AI or agents. You decide which calls an AI voice agent answers and which go to a team. Whoever picks up sees the customer and the chat history, and the AI hands over to a person with full context when the call needs personal attention.
Ask for permission in the chat. MonoChat workflows can ask for call permission in the conversation before an outbound call is triggered, and workflow automation can trigger calls from events, forms, reminders and CRM changes, such as appointment confirmations or payment reminder calls.
Summarize and sync. After each call, MonoChat can summarize the outcome, tag the intent and sentiment, and update your CRM or helpdesk.

If you also run a traditional phone line, MonoChat’s AI voice calls over SIP connect your SIP trunk for inbound and outbound calls with IVR, queues, routing rules, transcripts and an AI receptionist, in the same inbox as your chats. Larger teams can organize agents, skill-based routing and SLA dashboards with the multi-agent call center.

You can start on the free Basic plan (one agent, one channel) at app.monochat.ai, see the pricing page for other plans, or talk to us about calling availability for your number.

Sources

Put this into practice with MonoChat

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