Updated May 5, 2026: We have updated the timeline. Thank you for your patience.
[Introduction]
Brand Impersonation Protection for Teams Calling adds proactive safeguards against fraudulent or deceptive external callers who attempt to appear as trusted organizations. This helps reduce social-engineering risks and improves tenant security when users receive first-contact external calls. This update aligns with Microsoft’s ongoing investments in caller identity protection and secure collaboration.
This message is associated with Microsoft 365 Roadmap ID 543239.
[When this will happen:]
Targeted Release: Rollout will begin mid-May 2026 (previously early May) and is expected to complete by late May (previously late April).
General Availability: Timelines will be communicated in a future message.
[How this affects your organization:]
Who is affected:
- All organizations using Microsoft Teams Calling that receive inbound VoIP calls from first-contact external callers.
What will happen:
- Teams will evaluate inbound calls for signs of brand impersonation.
- Users will see high-risk call warnings before answering suspicious calls.
- Warnings may continue during the call if risk signals persist.
- Users can accept, block, or end the call.
- The feature will be enabled by default.
- Existing Teams Calling policies remain unchanged.
[What you can do to prepare:]
No admin action is required at this time.
- Inform helpdesk staff that users may begin seeing high-risk call warnings.
- Update internal training materials if applicable.
- Review Microsoft documentation on caller ID security when available.
Before rollout, we will update this post with new documentation.
[Compliance considerations:]
No compliance considerations identified, review as appropriate for your organization.