How to Set Up WhatsApp Coexistence: The Complete Step-by-Step Guide

What you need before you start

Before setting up WhatsApp Coexistence, make sure you have:

• A WhatsApp Business App already installed and active on your phone
• Access to Meta Business Manager (business.facebook.com)
• A ChatAgent account (free trial works fine)
• About 5 minutes of uninterrupted time

Step 1: Add your number to Meta Business Manager

This is the step most people skip – and it causes the most problems later. Before you connect anything through ChatAgent, you need to register your existing WhatsApp Business App number in Meta Business Manager.

Go to Business Settings, then WhatsApp Accounts, then Add. Select your country code and enter the phone number you already use in WhatsApp Business App. Meta will send a verification code to that number via WhatsApp.

Important: This does NOT remove your number from the WhatsApp Business App. It simply registers it with Meta’s business platform so the API can access it.

Step 2: Connect through ChatAgent Dashboard

Log into your ChatAgent dashboard at app.chatagent.so. Navigate to Integration, then WhatsApp, then Add Account.

You will see two options:

• “Keep WhatsApp Business App active (Coexistence)” – this is what you want
• “Use WhatsApp Business API only” – this is the regular API setup

Select Coexistence. You will be redirected to Facebook Login. Authorize ChatAgent to access your WhatsApp account.

Step 3: Choose chat sharing settings

ChatAgent will ask whether you want to share existing chats with the platform. This determines whether AI can see conversations that happened before setup.

Recommended: Enable chat sharing. This gives AI context about past conversations, which means better responses from day one. Without it, AI starts fresh – no history, no context.

Step 4: Test and go live

Once connected, send a test message to your WhatsApp number from a different phone. You should see it appear in both your WhatsApp Business App and the ChatAgent dashboard simultaneously.

If the message appears in both places, you are live. AI will start handling conversations based on your dashboard settings.

Common mistakes to avoid

• Skip Step 1: If you do not add your number to Meta Business Manager first, the connection will fail with a confusing error
• Use the wrong Facebook account: Make sure you are logged into the Facebook account that owns your WhatsApp Business App
• Forget to enable chat sharing: You can enable it later, but starting without history means AI makes more mistakes initially
• Test with the same phone: Always test from a different number to see the full customer experience

What happens after setup

Once live, every incoming message to your WhatsApp number goes through two paths simultaneously: your team sees it on the mobile app, and ChatAgent’s AI processes it through the API. If AI handles the conversation, your team still sees the full exchange on their phone. If they jump in on mobile, the API dashboard shows their responses too.

Both channels stay in sync. No message gets lost. No customer sees a delay.