How to Configure and Manage Shared Channels Across External Tenants in Microsoft Teams

Collaborating with external clients, vendor partners, and contractors in Microsoft Teams historically required switching tenants or adding guests to entire team spaces. Microsoft Teams Shared Channels (powered by Microsoft Entra B2B direct connect) eliminate tenant switching entirely. External partners can participate in conversations, share files, and co-author documents from within their own home tenant interface. Setting up cross-tenant shared channels requires configuration across both Microsoft Entra ID and Teams admin centres.

How Microsoft Teams Shared Channels Work

Unlike standard channels (open to all team members) or private channels (restricted to specific existing team members), shared channels can be shared with individual users or entire external teams without requiring guest account provisioning. Authentication occurs through mutual trust configured in Microsoft Entra (Azure AD) cross-tenant access settings, maintaining conditional access and data boundary compliance.

Step 1: Configuring Cross-Tenant Access in Microsoft Entra ID

Shared channels require bidirectional trust established between both Microsoft 365 tenants:

1. Sign in to the Microsoft Entra admin center as a Global Administrator or Security Administrator.
2. Navigate to External Identities > Cross-tenant access settings.
3. Click Organizational settings, then select Add organization.
4. Enter the domain name or tenant ID of your external partner organization.
5. Click the partner organization name, then select the Inbound access tab:
   • Under B2B direct connect, select Customize settings.
   • Set external users and groups to Allow access.
   • Under Applications, select Office 365 and Microsoft Teams.
6. Select the Outbound access tab and mirror the configuration, allowing your internal users to connect outwards to the partner tenant.
7. Ensure the external organization’s IT administrators complete reciprocal configuration in their tenant.

Step 2: Enabling Shared Channels in the Teams Admin Center

Once cross-tenant trust is active, verify Teams channel policies:

1. Open the Microsoft Teams admin center.
2. Expand Teams > Teams policies and select your active policy (e.g., Global (Org-wide default)).
3. Ensure the following settings are toggled On:
   • Create shared channels: Enabled
   • Invite external users to shared channels: Enabled
   • Join external shared channels: Enabled
4. Click Save. Changes propagate across Teams clients within a few hours.

Step 3: Creating and Sharing the Channel

Team owners can now create and distribute the shared channel:

1. In Microsoft Teams, navigate to your target team, click the More options (…) icon, and select Add channel.
2. Enter a channel name and description.
3. Under Privacy, select Shared – People you choose from your org or other orgs have access.
4. Click Create.
5. In the share dialog, enter the email address of the external collaborator (e.g., [email protected]).
6. Click Share and then Close.

The channel appears immediately in the external user’s Teams sidebar under a separate heading, clearly designated with a linked-channel badge, enabling seamless cross-tenant workflows without account switching.