Microsoft Teams: Control External Access by Domain for Specific Users and Groups

Gain granular control over external communication. By setting custom External Access policies, you can define domain allow/deny lists and assign them to specific users or groups - capabilities that were previously tenant-wide only ("Teams and Skype for Business users in external organizations"). Use this to pilot with a department, restrict high‑risk roles to approved partners, or open federation broadly where appropriate. Example: Allow Group A to communicate only with a specific domain, while Group B can communicate with all external domains.