Meta defines a conversation as a 24-hour message thread between a business and a customer. Conversations are opened when your business sends a template message or free-form message as described below.

Marketing/utility/authentication conversations

When you send an approved marketing, utility, or authentication template to a customer, Meta checks for an existing open conversation in the same category. If one exists, no new conversation will be opened. Otherwise, a new conversation in that category will open and remain open for 24 hours.

For examples, see here.

Service conversation

When you send a free-form message to a customer (which you can only do if a customer service window exists between you and the customer), Meta checks for an existing open conversation of any category. If one exists, no new conversation will be opened. Otherwise, a new service conversation will open and remain open for 24 hours.

For examples, see here.

Multiple conversations

You can have multiple open conversations with a customer at the same time. This can occur in two scenarios:

1. You have an existing open marketing, utility, or authentication conversation with a customer and send a template message from a different category within 24 hours.

2. You have an existing open service conversation with a customer and send a template message within 24 hours.

Free Entry Point Conversations

A free entry point conversation is opened if a customer contacts you via a Click to WhatsApp Ad button and you respond within 24 hours. If you do not respond within 24 hours, a free entry point conversation is not opened and you must use a template to message the customer. The free entry point conversation is opened as soon as your message is delivered and lasts 72 hours. Once the free entry point conversation is opened, you can send any type of message to the customer without incurring additional charges. However, you can only send free-form messages if there is an open customer service window between you and the customer.

For more information, see:

• Opening conversations (Meta)

• What conversation categories are available in WhatsApp?

• How does WhatsApp's conversation-based pricing work?