Can Global Address Lists Be Merged Across Microsoft 365 Tenants?
Question details
Organizations with multiple Microsoft 365 tenants want to know if they can combine their Global Address Lists to make users searchable across tenants in Microsoft Teams.
- Product
- Microsoft 365
- Device & OS
- not provided
- Scenario
- Managing contacts and facilitating communication across multiple Microsoft 365 tenants for a unified organizational directory.
- Observed behavior
- Each tenant has its own separate Global Address List, making it impossible to search for users in other tenants without additional configuration or external synchronization.
Confirm whether your organization is strictly limited to using native Microsoft 365 features, or if you have the budget and administrative approval to integrate third-party synchronization tools.
Use Third-Party Synchronization Tools
Because Microsoft does not provide a native method to merge GALs across tenants, utilizing a specialized third-party directory synchronization tool is the standard workaround.
Microsoft 365 architecture isolates Global Address Lists (GAL) by tenant to maintain strict security and data privacy. Consequently, there is no built-in capability to natively merge or continuously synchronize address lists between two separate tenants.
To achieve cross-tenant contact synchronization and allow seamless user searches within Microsoft Teams, administrators must evaluate, select, and deploy third-party GAL synchronization solutions.
Determine exactly which contacts, departments, and attributes (such as email, phone number, and Teams presence) need to be visible across your Microsoft 365 tenants.
Evaluate and choose a reliable third-party GAL synchronization software available on the market that fits your organization's enterprise architecture.
Grant the synchronization tool the necessary Azure Active Directory (Microsoft Entra ID) permissions and API access for all participating tenants.
Define the mapping, synchronization frequency, and conflict resolution rules within the tool's dashboard to ensure contact directories are kept up to date.
Enable External Access in Microsoft Teams
If your primary goal is simply to allow users to message and search for individuals in the other tenant via Teams, configuring External Access is a native alternative to merging the GAL.
Enhance Your Productivity with WPS Office
While navigating the complexities of Microsoft 365 tenant management, you can simplify your daily document workflow with WPS Office. It provides a lightweight, highly compatible, and cost-effective alternative for all your spreadsheet, document, and presentation needs.
- 1. Download the software: Visit the official WPS Office website and download the free installation package for your operating system.
- 2. Install WPS Office: Run the downloaded installer and follow the on-screen instructions to complete the setup.
- 3. Start creating and editing: Open WPS Office to instantly view, edit, or create documents, spreadsheets, and presentations with full Microsoft format compatibility.
Frequently Asked Questions
Why can't I search for a user in another tenant on Microsoft Teams?
By default, Microsoft Teams restricts directory searches to your own tenant's Global Address List. Unless External Access is configured or a cross-tenant directory synchronization is established, users from other tenants will not appear in standard searches.
Does Azure AD B2B collaboration merge Global Address Lists?
No. Azure AD B2B collaboration allows you to invite guest users into your directory so they can access resources and channels. While this makes those specific guests visible in your tenant, it does not merge the two complete Global Address Lists.
Are there any native Microsoft tools specifically for merging tenant GALs?
Currently, Microsoft does not offer a native, out-of-the-box tool designed specifically to merge or continually synchronize separate Global Address Lists across different Microsoft 365 tenants.
