Putting ChatGPT behind your WhatsApp Business number lets customers message you the way they already message everyone else, and get an answer at 2am. Connect WhatsApp to Social Intents, route the number to a chat widget, choose an OpenAI model, and train it on your business content.
Unlike the Claude and Gemini guides, this one has no API key step. GPT-6 Luna, GPT-5.6 Luna, GPT-4o and GPT-4o Mini are included in your plan, so you can have a working WhatsApp assistant without an OpenAI account.
What This Integration Does
Customers message your business number on WhatsApp. ChatGPT answers from the knowledge you trained it on, and your team picks up the conversation in the Social Intents Inbox or in Microsoft Teams, Slack or Google Chat when a person is needed.
The chat widget is where your AI agent, knowledge and routing come together. WhatsApp is the customer's entry point, but you configure the widget.
Before You Start
- A plan that includes WhatsApp: the free trial, Basic, Pro or Business.
- A chat widget for the team you want to connect. See Set Up Your First Chat Widget.
- Admin access to the Meta business portfolio you will connect, a number that can receive an SMS or voice call, and a payment card for WhatsApp Manager.
- A number that isn't active on personal WhatsApp or with another provider. A WhatsApp Business app number can stay in the app with coexistence.
- Current FAQs, product documentation and policies for the assistant to learn from.
No OpenAI API key is required for the included models. If you want GPT-5.6 or another bring your own key model, have your own OpenAI API key ready. See Choosing Your AI Engine.
Connecting WhatsApp to ChatGPT
1. Connect Your WhatsApp Business Number
Go to Integrations, click Connect on the WhatsApp card, read the Before you continue to Meta checklist and click Continue to Meta. In Meta's window, choose your business portfolio and WhatsApp Business Account and verify the number (or scan a QR code to keep the WhatsApp Business app; see coexistence). When you're back, work through the Finish setup checklist, starting with a payment method in WhatsApp Manager. Full detail is in Setting Up WhatsApp Business.
2. Route the Number to a Chat Widget
Go to Settings > Channels and expand WhatsApp. Under WhatsApp numbers, choose the widget for your number and click Save channel settings. The AI agent, knowledge and escalation rules all come from that widget. Running more than one number? See Multiple WhatsApp Numbers.
3. Select an OpenAI Model
Open Chat Widgets > your widget > AI Agent, choose ChatGPT as the provider and pick a model:
| Model | Notes | API key |
|---|---|---|
| GPT-6 Luna | The default. Most efficient current model, 1M token context window. | Included |
| GPT-5.6 Luna | Budget friendly, 1M context. Good for short, factual answers at high volume. | Included |
| GPT-4o and GPT-4o Mini | Fast; useful if your instructions are already tuned for them. | Included |
| GPT-5.6 | Best quality, 1M context. | Your own key |
| GPT-5.6 Terra | Balanced intelligence and cost, 1M context. | Your own key |
| GPT-5.2, GPT-4.1, GPT-4.1 Mini, GPT-4 | Earlier models, kept for existing bots. | Your own key |
Start with GPT-6 Luna. It's included, fast enough for messaging, and you can change model later without redoing any WhatsApp setup. Bring your own key models need your OpenAI API key in the API key field on the same tab, and OpenAI bills you for that usage.
4. Train It on Your Business
Add your website, help center, PDFs and spreadsheets under Data sources on the widget's AI Agent tab. WhatsApp answers are read on a phone, so keep sources tight and current. See Training Your Chatbot on Content.
Then write your instructions. Ask for short paragraphs, no tables, and a clear next step in every reply. WhatsApp shows plain text, so formatting that looks fine in a web widget reads badly in a phone thread. See Writing System Instructions.
5. Set Up Human Handoff
On the widget's Handoff tab, decide when ChatGPT should stop and a person should take over: an explicit request for a human, billing and cancellation topics, complaints, or questions it can't answer from your content. Confirm the receiving channel is one your team watches. See Escalation to Human Agents.
6. Test the Whole Path
Message the business number from a real phone. Check the answer is accurate, that escalation fires, and that the handoff lands in the right Inbox or channel. Also ask something the assistant has no source for and check it offers a person instead of guessing.
WhatsApp Session Rules and Costs
When a customer messages you, you have 24 hours to reply with normal messages. Outside that window you can only send an approved template. The AI agent answers inside the window, so this rarely affects it, but it does affect follow-ups. See WhatsApp Templates, Media & Sessions.
Budget for your Social Intents plan and Meta's charges. Meta prices WhatsApp per delivered message, by category and country, and bills your WhatsApp Business Account directly. Since October 1, 2026, replies inside the 24-hour customer service window, including AI replies, are free for the first 1,000 service messages per business number each month, then charged at a per-country rate. If you choose a bring your own key model such as GPT-5.6, add OpenAI usage as a third line.
Troubleshooting
The number connected but no messages arrive. Check the number has a widget in Settings > Channels > WhatsApp, and that the Finish setup checklist shows the number connected. See WhatsApp Setup Troubleshooting.
Messages arrive but the AI never answers. Confirm the AI agent is turned on for that specific widget. Settings are per widget.
The AI answers, but badly. This is almost always knowledge rather than model. Check which sources are trained, read the transcript, and tighten your instructions before reaching for a larger model.
A bring your own key model returns an authentication error. Re-enter your OpenAI API key on the AI Agent tab and check the key is active and funded. The included models don't have this failure mode.
Handoffs go nowhere. Verify the escalation destination and that someone is monitoring it. See Troubleshooting Missed Chats.
Frequently Asked Questions
Do I need an OpenAI API key to connect WhatsApp to ChatGPT?
Not for GPT-6 Luna, GPT-5.6 Luna, GPT-4o or GPT-4o Mini. Those are included in your plan. You only need your own OpenAI key for models such as GPT-5.6 or GPT-5.6 Terra, and OpenAI bills you directly for that usage.
Which plan do I need for WhatsApp?
WhatsApp is available on Basic and above, and during the free trial. Basic includes one WhatsApp number, Pro five and Business ten. See Plans, Billing and Upgrades.
Can I keep using WhatsApp on my phone with the same number?
Yes, if the number is in the WhatsApp Business app. Use coexistence during signup. Personal WhatsApp numbers must be moved off the app first.
Can a human take over mid conversation?
Yes. When escalation fires, or an agent joins, the AI steps back and your team replies from the Inbox or your team platform. The customer stays in the same WhatsApp thread.
Can ChatGPT answer replies to my WhatsApp broadcasts?
Yes. Broadcast replies route like any WhatsApp message, so the widget's AI agent answers first. See WhatsApp Broadcasts.
Can I use ChatGPT on WhatsApp and a different model on my website?
Yes. Model choice is per widget. Route WhatsApp to one widget with ChatGPT and keep another widget on a different model.