Now Admins Can Block External Users in Microsoft Teams From Defender Portal

Microsoft will allow administrators to manage blocked external users in Teams via the Tenant Allow/Block List in Microsoft Defender for Office 365, centralizing external access controls across services. The capability—rolling out worldwide between early and mid-January 2026—supports blocking up to 4,000 domains and 200 individual email addresses, includes audit logging, and requires Defender for Office 365 Plan 1 or 2.