The naming convention here is not very clear/strict here, with Microsoft using different terms in different places, but there are essentially two Teams worlds.
- Teams Work / Teams Commercial / Office 365 / Teams Enterprise / Teams Business / “Teams at Work” using an Azure AD account are one group
- Teams Personal / Teams Consumer / Teams for life / “Teamas accounts not managed by an organisation” / Teams for Home using a consumer Microsoft Account (Outlook account / hotmail account if you go back that far)
I’ll stick with Teams Work and Teams Personal for ease. Previously, these two worlds were separate. While a work account in company A could chat and call a work account in company B, Work and personal accounts could not directly communicate. Now Teams Consumer users can Chat with Teams Commercial users. Meaning you can use your work account to talk to friends and family, maybe even some SMBs on their Consumer accounts. We used to call this “Federation” in Skype for the business world, but that term seems to have dropped out of fashion a bit. This functionality has been available between Teams Work and Skype Consumer/Personal accounts for some time.
How does Teams Work to Teams Personal Chat work?
A chat can be started in either direction.
- Teams Work users can start a chat with Teams personal users by entering their email or phone number
- Teams personal users can enter the users Teams work email and start a chat
This works in a 1:1 or an existing group chat (not channels). Rich text formatting GIFs and media are supported. There is no voice or video calling.
Users on both sides have the option to decline the external invitation. One can message an external user up to 10 times before they accept. If the message is not accepted after 10 messages, you won’t be able to send additional messages to this user.
Interestingly if you invite someone who doesn’t have a Teams account, they will receive an email or a text message inviting them to join the conversation using a personal account. If they register and sign in to their Teams personal account, they’ll be able to join the chat.
It is worth noting that this functionality is on by default. Teams Work Admins can choose to allow or block both outgoing chat requests to Teams Personal and incoming chat requests for Teams Personal, either globally or on a per-user basis. For example, blocking important Work or high profile work uses from receiving incoming chat invites from Teams Personal users. Teams personal account users can manage their discoverability in their settings menu and opt-out from being discoverable by other Teams users.
Tenant level: CsTenantFederationConfiguration
User level: CsExternalAccessPolicy
There are also several checks and controls:
- Explicit opt-in on a per chat basis: end users are not shown messages unless they click to preview, are reminded of the risks of external chat, and are asked to explicitly accept or block the message request.
- External chat warnings: visible in both the chat list and chat header.
- Spam checks: prior to an explicit ‘accept’, every message sent by a Teams personal account goes through runtime spam checks. If spam is detected, the chat message is not delivered.
- Message limits: messages prior to an explicit ‘accept’ are limited to 10. Additional messages are not delivered.
- Only name and email address are displayed, no other identifiers like profile pictures.
It appears this functionality is now being branded under “Teams Connect”, which I thought was previously just an alternate marketing brand for Shared Channels (still to be released)
- Microsoft 365 Roadmap ID 88381
- Message Center MC296208
- Microsoft docs: Manage external access in Microsoft Teams
- Microsoft blog: Microsoft Teams users can now chat with any Teams user outside their organization
Thanks Tom. Great write up. This is the only page on the entire internet that mentions “There is no voice or video calling.” Surely this is a trivial setting inside the backend of Microsoft – I mean you can video chat Teams for Work with an old Skype Home user & Teams for Home with Skype. What’s the deal?