Importing Approved Domains to Teams Admin Centre External Access

Learn how to import approved domains into Microsoft Teams External Access, whether you are adding a single entry manually or running a bulk update via PowerShell. By managing this list, you control exactly which external organizations can chat with your users, ensuring you stay secure without blocking business.

While adding a domain one-by-one in the Admin Center works for quick fixes, a bulk import is the only way to go if you have a long list of partners to add at once. For IT admins, keeping this "allow list" synchronized is a routine and essential task, particularly if you have configured your tenant to block all external domains by default.

How to do this manually:

1. To do this manually, you first need to go to the Teams Admin Centre and login.

2. Once you are logged in, you need to go to Users > External Access

3. 

   In 'Organization settings' as long as 'Block only specific external domains' is enabled, you should have a button to 'Add external domains to the blocked list.

4. 

   You can then add any domain you would like to add manually.

   

   
   

Using a PowerShell script to do this:

Adding approved domains manually in the Teams Admin Centre is straightforward for a handful of partners, but it quickly becomes unmanageable when dealing with dozens or hundreds of entries. Clicking through the UI for every single domain is tedious, time-consuming, and prone to human error. For IT administrators managing large partner lists, using PowerShell is the superior approach. It allows you to bulk import an entire list of domains in seconds, ensuring your external access policies are updated instantly and accurately without the manual grind.