WhatsApp messaging is regulated by Meta rules.
This means you cannot always message a customer freely. It all depends on who started the conversation and whether the WhatsApp session is still active.
This guide explains the difference between:
Inbound WhatsApp conversations
Outbound WhatsApp conversations
What you are allowed to send and when
An inbound conversation happens when the customer messages your business first.
Once the customer sends a WhatsApp message:
the conversation becomes active and is visible in the Waiting list
The chat is assigned to a user based on the incoming flow configuration
the users can reply with a free-form text message within the 24-hour Customer Service Window (CSW)
After the user’s reply, the conversation will be moved to Open
The users can keep sending free-form messages after every client’s reply within the CSW
If the CSW (24 hours) expires, the chat will be moved to Expired
Once expired, the chat can be reopened by sending a pre-approved template
An outbound conversation happens when your business wants to message the customer first.
This is used for:
appointment reminders
payment follow-ups
delivery updates
sales follow-ups
customer support updates
Outbound messaging is more restricted and requires an approved template.
The user must send an approved WhatsApp Template (The chat will be visible under Waiting)
Once the client replies, the chat will be moved to Open, and the CSW will start
The user can reply with a free-form text within the CSW (24 hours)
If no reply is sent within 24 hours, the conversation will fall under Expired
If the chat expired, the user will need to reopen the conversation with a pre-approved template
When the CSW expires:
the conversation is marked as Expired
the agent cannot send free-form messages
the only way to reopen the conversation is by sending a template
You now know the difference between inbound and outbound WhatsApp messaging:
Inbound = customer starts → free-form replies allowed (CSW active)
Outbound = business starts → template required
Expired chat = CSW ended → template required again