By default, Scale AI supports up to two WhatsApp numbers in one Workspace; to connect more, contact the Scale team. Both numbers share the same Inbox, contacts, AI assistant and reports, and every conversation is answered from the number the customer wrote to. A common setup is one number for Support and one for Sales, each with its own team.
This guide explains how to add and name a second number, filter the Inbox by number, give each number its own team, import WhatsApp Business app chat history, and what happens with customers who use a WhatsApp username. To connect your first number, see How to connect WhatsApp Business to Scale.
What multiple WhatsApp numbers are in Scale AI
Multiple WhatsApp numbers means one Scale AI Workspace receives and answers messages on two WhatsApp Business numbers at the same time. The two numbers are not two separate businesses: they share one contact list, one AI assistant with the same training, one subscription and one set of reports. If you need fully separate businesses, use one Workspace for each — see Workspaces in Scale.
One number is the Primary number and the other is the second number. Both answer customers in the Inbox. The Primary number is also the one Scale uses for campaigns, message templates, the Scale API and Meta Ads conversion tracking.
| Feature | Primary number | Second number |
|---|---|---|
| Receives messages and answers them in the Inbox | Yes | Yes |
| Has its own name and its own team | Yes | Yes |
| Answered by the AI assistant | Yes | Yes |
| Sends campaigns, templates and Scale API messages | Yes | No, these go out from the Primary number |
Two WhatsApp numbers per Workspace by default
Can I connect two WhatsApp numbers to one Scale AI Workspace? Yes. By default, Scale AI supports up to two WhatsApp numbers per Workspace, the Primary number included. To connect more numbers to the same Workspace, contact the Scale team to raise the limit.
Scale's servers enforce each Workspace's limit, not only the screen. When a Workspace reaches its limit, the Add WhatsApp Number button is disabled, and with the default limit the card reads “Maximum 2 WhatsApp numbers per Workspace. Contact the Scale team to add more.” Any further number is refused even if someone tries to add it another way. Disconnecting a number frees its place.
A WhatsApp number belongs to one Workspace at a time.
How to add a second WhatsApp number
Open Settings → Channels
The WhatsApp card lists your connected number under WhatsApp Numbers. Only the account owner sees this card.
Press Add WhatsApp Number
The same Meta window you used for your first number opens, with a note that the new number joins this Workspace beside the current one.
Name the numbers
Type a name for the new number, for example Sales. If your current number has no name yet, Scale asks for one too, for example Support.
Complete the Meta window
Sign in with Meta, choose the WhatsApp Business account and verify the number, exactly as for the first number. If the number runs in the WhatsApp Business app, you can keep using the app on your phone.
Check the list
Back in Settings → Channels, both numbers appear with their names and status, with Primary next to the main one.
Naming your numbers: a Support and Sales example
A number name is an internal label for your team. Customers never see it; they see your WhatsApp Business profile as usual. A name is 1 to 40 characters and must differ from the Workspace's other number. To change it, press Rename on the number in Settings → Channels. Renaming never changes the phone number or its conversations.
Example: a clinic names its first number Support for appointments and questions, and its second number Sales for new offers. The team then sees where each message came from:
| Where | What your team sees |
|---|---|
| Inbox filters | All Numbers, then Support, then Sales |
| Top of the conversation | Via Sales |
| Reply box | Reply via Support |
| Settings → Channels | 1. Support, Primary, then 2. Sales |
Filtering WhatsApp conversations in the Inbox by number
When a Workspace has two numbers, the Inbox shows number filters above the conversation list: All Numbers, then one filter per number name. Choosing Sales shows only the Sales number's conversations, and the counts and unread markers follow the filter. The same choice applies to the number filter on Home. A team member who works only one number does not see the filters.
On Home, everything is counted once: a lead on the number the customer first wrote to, a sale on the number of the conversation where it was recorded, and a message on the number it was sent from or received on. All Numbers is the sum of the two. For the rest of the Inbox, see the Inbox guide.
WhatsApp number teams and lead routing
Assign team members to a number
By default, every team member can work both numbers. To limit a number, press Manage Team on it in Settings → Channels, choose Only selected team members and tick the people who work that number. The owner always sees every number.
A team member outside a number's team cannot open that number's conversations, cannot reply from it and is not alerted about it. Scale's servers check this on every request; it is not just hidden on screen. Each team member still sees only the leads assigned to them, as before. To add or manage team members, see Managing your team.
How leads are routed between numbers
- A new customer who writes to a number is assigned within that number's team, using your usual distribution settings
- If an existing customer writes to a number their agent cannot work, the conversation moves to that number's team, and the conversation timeline says why
- If nobody on that team is available, the lead waits with the owner instead of going to someone outside the team
- When you change a number's team, conversations whose agent can no longer see that number move to the new team
One customer on both numbers
When the same customer writes to both numbers, Scale keeps one contact and one lead for them, with one conversation per number. Their sales and notes stay on the same customer record. Scale recognises customers by their exact phone number inside the Workspace only, never by name, so two people with similar names stay separate.
Each number has its own unread state: reading a customer's Support conversation leaves a newer Sales message from the same customer unread.
Replies always leave from the correct number
Scale sends every reply from the WhatsApp number of its conversation, so a customer never gets an answer from a number they did not write to.
- The AI assistant replies from the number the message arrived on
- In the Inbox, a reply goes from the number shown next to Reply via above the message box
- When the Inbox is filtered by a number, replies go from that number
- When a customer has conversations on both numbers, the owner can pick the number under Reply via; a team member can pick only numbers on their team
- WhatsApp's 24-hour reply window is counted for each number separately
WhatsApp Coexistence chat history and Share chats
Coexistence means your number keeps working in the WhatsApp Business app on your phone while it is also connected to Scale. Share chats is the choice the WhatsApp Business app shows during the connection: it allows Meta to send Scale your recent one-to-one chat history.
Scale asks Meta for that history automatically right after the number connects. Meta then sends it in parts, usually within minutes to a few hours. Settings → Channels shows the progress on the number: requested, importing, imported, or declined.
| Question | Answer |
|---|---|
| How far back does the history go? | Up to 180 days of one-to-one chats |
| Are group chats imported? | No, Meta never sends group chats |
| Are photos and files imported? | Only those from the last 14 days; older media is not available from Meta |
| Does the AI reply to old messages? | No. Imported messages are a record only: no AI reply, no message charge, no unread marker and no notification |
| Where do the chats appear? | In each customer's conversation, with the original dates and a WhatsApp history label |
| Who gets new contacts from the history? | They stay with the owner until you assign them |
Customers who use a WhatsApp username (BSUID)
WhatsApp lets people use a username and hide their phone number. For those customers, Meta sends a business-scoped user ID (BSUID) instead of a phone number. A BSUID is an ID that Meta creates for one customer and one business portfolio; it is not a phone number.
Scale keeps these conversations working. The customer appears by their username, or as WhatsApp user, and you reply from the Inbox as usual. The username is for display only and is never used to recognise customers. If the customer later shares their phone number, Scale keeps the same contact and conversation.
- Username-only customers are left out of campaigns, and the Scale API cannot send to them
- The shortcut that opens the chat in WhatsApp is hidden for them, because there is no phone number to open
- If your two numbers are in different Meta business portfolios, the same person may appear as two contacts, because Meta gives them a different ID in each portfolio
Security and Scale AI WhatsApp permissions
Scale protects a multi-number Workspace with checks on its servers, not only on screen:
- Data is isolated by Workspace: one Workspace's numbers, conversations, messages and contacts are never shown to another
- A team member reaches only the numbers whose team includes them, and only the leads assigned to them
- A team member cannot open or reply to another team's conversations
- Every message is sent from the WhatsApp number of its conversation
- WhatsApp access tokens and other connection credentials are never sent to team members, and the dashboard never shows them in full to anyone
- Each Workspace's number limit is enforced by Scale's servers, so it cannot be bypassed from the browser
- The owner has Workspace-wide management access: numbers, names, teams and disconnecting
Owner vs Agent access
| Action | Owner | Agent |
|---|---|---|
| Add a number, disconnect it or make it Primary | Yes | No |
| Rename a number or change its team | Yes | No |
| See conversations | Every number | Their team's numbers and their own leads only |
| Reply to customers | From either number | Only from their team's numbers |
| Use the Inbox number filters | Every number | Their numbers only |
| See WhatsApp access tokens | Never shown in full | No |
What happens when you disconnect a number
| Situation | What happens |
|---|---|
| You disconnect the second number | It stops receiving and sending. Its conversations and history stay in the Inbox, and its place is free for another number |
| You disconnect the Primary number while the second is connected | The second number becomes the Primary number automatically, so the Workspace keeps working |
| You disconnect the only number | WhatsApp is disconnected from the Workspace. Conversations stay |
| You reply in a conversation whose number was disconnected | Scale sends from the Primary number instead; WhatsApp may ask for a template message first, because the customer has not written to that number |
Important limitations
- A Workspace holds up to two WhatsApp numbers by default; contact the Scale team to raise the limit
- A WhatsApp number belongs to one Workspace only
- Campaigns, message templates, the Scale API and Meta Ads conversion tracking use the Primary number
- Chat history can be requested only once, within 24 hours of connecting, and covers up to 180 days of one-to-one chats
- Numbers connected before chat history import was available must be reconnected from the WhatsApp Business app to import their history
- Username-only customers cannot receive campaigns or Scale API messages
- Number names are internal; customers see your WhatsApp Business profile
Frequently asked questions
Can I connect two WhatsApp numbers to one Scale AI Workspace?
Yes. By default, Scale AI supports up to two WhatsApp numbers per Workspace. Add the second one in Settings → Channels with Add WhatsApp Number.
Can I add a third WhatsApp number to the same Workspace?
Not on your own. The default limit is two numbers per Workspace, including the Primary number. To connect a third number, contact the Scale team to raise the limit.
Can the same WhatsApp number be used in two Workspaces?
No. A WhatsApp number belongs to one Workspace at a time. Disconnect it from the first Workspace before connecting it to another.
Which number does Scale reply from?
From the number of the conversation. The AI assistant replies from the number the customer wrote to, and a team reply goes from the number shown next to Reply via.
Can an agent see conversations on a number that is not assigned to them?
No. An agent sees only the numbers whose team includes them, and only the leads assigned to them. The owner sees every number.
Does the AI reply to imported chat history?
No. Imported WhatsApp history is a record only. The AI assistant does not reply to it, and it is not charged.
What is a WhatsApp BSUID?
A BSUID is the business-scoped user ID Meta sends instead of a phone number when a customer uses a WhatsApp username. Scale uses it to keep the conversation and shows the customer by their username.
Can agents see WhatsApp access tokens?
No. Access tokens are never sent to agents, and the dashboard does not show them in full to anyone.
Troubleshooting
| Problem | Likely cause | What to do |
|---|---|---|
| Add WhatsApp Number is disabled | The Workspace has reached its number limit, two by default | Disconnect a number, or contact the Scale team to raise the limit |
| The number is refused as already in use | It is connected to another Workspace | Disconnect it in that Workspace first |
| Chat history stays on requested | Meta has not sent it yet | Wait a few hours; Meta sends history in parts |
| Chat history says the request failed | The request did not reach Meta | Press Request history again on the number, within 24 hours of connecting |
| Chat history says sharing was declined | Don’t share chats was chosen on the phone | Disconnect in the WhatsApp Business app, connect again and choose Share chats |
| An agent cannot find a conversation | They are not on that number's team, or the lead belongs to someone else | Check Manage Team on the number and the lead's assigned agent |
| A reply went from the other number | Reply via showed the other number | Check Reply via before sending, or filter the Inbox by number |
| A customer shows as WhatsApp user | The customer uses a WhatsApp username | Reply as usual; their number appears if they share it later |
Still stuck? Contact Scale support.
Safe production setup
Related guides: How to connect WhatsApp Business to Scale, Managing your team, the Inbox guide, Workspaces in Scale and Scale Settings.