Short answer: to run WhatsApp, Instagram and Messenger from one team inbox, connect all three channels to a shared inbox tool. Give every conversation one owner through assignment, and write the rules down: who answers what, how fast, and when a bot hands over to a person. The part teams most often get wrong isn't the software. It's Meta's reply windows, which decide when you're even allowed to answer.
This guide is the checklist we'd follow to set up a shared inbox for a small support or sales team.
Why one inbox beats three apps
When customers can reach you on WhatsApp, Instagram and Messenger, each channel usually ends up on a different phone or browser tab. Messages get missed, two people answer the same customer, and nobody can see the full history.
A shared inbox fixes three things:
- Nothing is missed. Every message from every channel lands in one list.
- Nobody double-answers. Assigning a conversation shows who owns it.
- Context travels with the customer. Notes, labels and past orders sit next to the chat, whoever picks it up.
Step 1: Connect the channels
- WhatsApp: connect through the WhatsApp Business Platform (API). If the number is already on the WhatsApp Business app, you can keep using the app alongside it (see WhatsApp Business app vs API).
- Instagram: the account must be an Instagram professional account (Business or Creator) linked to a Facebook Page you manage.
- Messenger: connect the Facebook Page, which needs a Page admin.
In Omni, this is covered in Connect WhatsApp Business and Connect Messenger and Instagram.
Step 2: Learn the reply windows before your first busy day
Each channel limits when a business may reply:
| Channel | Free-form replies allowed | After the window closes |
|---|---|---|
| 24 hours after the customer's last message | Only approved templates (charged) | |
| 24 hours after the customer's last message | Nothing, unless a person replies within 7 days using Meta's Human Agent tag (needs Meta approval) | |
| Messenger | 24 hours after the customer's last message | Same as Instagram, plus some Messenger-only message tags |
Two rules matter most for a team:
- Answer inside 24 hours, every time. A message left over the weekend can become one you can't reply to at all on Instagram or Messenger.
- You can't start an Instagram or Messenger DM. The customer has to write first.
More detail: Instagram's 24-hour messaging window, explained.
Step 3: Decide who owns what
Write these down and share them with the team:
- Default owner: are new conversations unassigned until someone picks one up, or routed straight to a person?
- Response-time target: for example, a first reply within 1 hour during business hours. It has to be well inside the 24-hour window.
- Hand-offs: when sales passes a customer to support, reassign the conversation and leave an internal note. Don't start a new chat.
- Resolving: mark a conversation resolved when it's done. It reopens automatically if the customer writes again.
Step 4: Set up the time-savers
- Canned replies for the ten questions you answer every day: prices, opening hours, delivery times, returns.
- Labels such as
order-issue,leadorvip, so the team can filter and you can report on them later. - Internal notes for anything a colleague needs to know. Customers never see them.
Step 5: Add automation, carefully
Start small:
- An out-of-hours reply that says when a person will answer.
- An AI chatbot for the routine questions, trained only on your own FAQs, policies and product information, so it doesn't invent answers. See AI chatbots and knowledge bases.
- A clear hand-off. The bot passes the conversation to a person when it can't help or when the customer asks for one.
From October 2026, WhatsApp charges for each service message on the API (pricing explained). Set your bot to answer in one complete message rather than several short ones.
Step 6: Review weekly
Check four things once a week:
- First-response time by channel and by agent.
- Conversations that hit the 24-hour limit without a reply. Each one is a customer you may have lost.
- Top labels, which tell you what customers keep asking about. Add those answers to your FAQ and chatbot.
- Bot hand-off rate. If most bot conversations end in a hand-off, the knowledge base is missing something.
A starter checklist
- WhatsApp, Instagram and Messenger connected
- Everyone on the team knows the 24-hour rule
- Assignment rule and response-time target written down
- 10 canned replies and 5 labels created
- Out-of-hours reply switched on
- AI chatbot limited to your own content, with a hand-off to people
- Weekly 15-minute review in the calendar
Related guides: Team inbox · Automations · Workspaces and team members
Frequently asked questions
Can several people answer the same WhatsApp number?
Yes, through the WhatsApp Business Platform (API) and a shared inbox. Everyone works from one number, and each conversation is assigned to one person.
Can I reply to an Instagram DM after 24 hours?
Only if a person replies within 7 days using Meta's Human Agent tag, which requires the sending app to have Meta's approval. Otherwise you have to wait for the customer to message again.
What should a chatbot answer in a shared inbox?
Routine questions answered from your own FAQs, policies and product information, with a hand-off to a person when it cannot help or the customer asks for one.
- #shared inbox
- #messenger
The Omni Team
The Omni team builds the shared inbox, AI chatbots and automation tools businesses use to talk to customers on WhatsApp, Instagram and Messenger.
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