(Updated) Microsoft Outlook | Outlook Mobile: New unverified sender banner in reading pane

Message Center ID: MC1112452
Microsoft 365 apps
Stay Informed
Feature update User impact
July 2025 August 2025 September 2025 October 2025
Android iOS

Summary

Outlook Mobile will show a new banner in the reading pane for emails from unverified senders, warning users about potential impersonation. This feature, rolling out July to October 2025, aligns with desktop and web versions and requires no admin action, though user awareness is recommended.

Details

Updated September 23, 2025: We have updated the timeline. Thank you for your patience. 

 We’re introducing a new visual indicator in the reading pane of Outlook Mobile (iOS and Android) to help users identify messages from unverified senders. This feature aligns with existing functionality in Outlook for desktop and web, bringing a consistent experience across platforms. When a message is from a sender we couldn’t verify as safe, users will see a banner in the reading pane warning them to be cautious.

This message is associated with Microsoft 365 Roadmap ID 491471.

[When this will happen:]

General Availability (Worldwide): We will begin rolling out mid-July 2025 and expect to complete by late October 2025 (previously mid-September).

[How this will affect your organization:]

When users receive an email from an unverified sender, they will see a banner in the reading pane explaining why the sender is flagged and warning about potential impersonation. This complements existing safety messages such as:

  • “External sender”
  • “Not on safe senders list”
  • “You don’t often get email from this sender”

This feature is available by default when the unverified signal is received by the service. There are no admin controls to configure or disable this functionality.

[What you need to do to prepare:]

No admin action is required. However, we recommend informing your users about this new visual cue and its purpose. If your organization provides internal training or documentation on email safety, consider updating it to include this new banner.

Learn more: Phishing and suspicious behavior in Outlook

Related Roadmap Items

Change History

October 6, 2025 at 10:30 PM Updated
Last Updated Date
Previous
2025-09-23T15:48:31.473Z
New
2025-10-06T21:37:27.940Z
September 23, 2025 at 4:30 PM Updated
Summary
Previous
Outlook Mobile will display a new banner in the reading pane warning users about emails from unverified senders, aligning with desktop and web versions. Rolling out worldwide from mid-July to mid-September 2025, this feature is automatic with no admin controls. Users should be informed accordingly.
New
Outlook Mobile will show a new banner in the reading pane for emails from unverified senders, warning users about potential impersonation. This feature, rolling out July to October 2025, aligns with desktop and web versions and requires no admin action, though user awareness is recommended.
Last Updated Date
Previous
2025-08-19T16:22:12.490Z
New
2025-09-23T15:48:31.473Z
Body Content
Previous

Updated August 19, 2025: We have updated the timeline. Thank you for your patience.

We’re introducing a new visual indicator in the reading pane of Outlook Mobile (iOS and Android) to help users identify messages from unverified senders. This feature aligns with existing functionality in Outlook for desktop and web, bringing a consistent experience across platforms. When a message is from a sender we couldn’t verify as safe, users will see a banner in the reading pane warning them to be cautious.

This message is associated with Microsoft 365 Roadmap ID 491471.

[When this will happen:]

General Availability (Worldwide): We will begin rolling out mid-July 2025 and expect to complete by mid-September 2025 (previously mid-August).

[How this will affect your organization:]

When users receive an email from an unverified sender, they will see a banner in the reading pane explaining why the sender is flagged and warning about potential impersonation. This complements existing safety messages such as:

  • “External sender”
  • “Not on safe senders list”
  • “You don’t often get email from this sender”

This feature is available by default when the unverified signal is received by the service. There are no admin controls to configure or disable this functionality.

[What you need to do to prepare:]

No admin action is required. However, we recommend informing your users about this new visual cue and its purpose. If your organization provides internal training or documentation on email safety, consider updating it to include this new banner.

Learn more: Phishing and suspicious behavior in Outlook

New

Updated September 23, 2025: We have updated the timeline. Thank you for your patience. 

 We’re introducing a new visual indicator in the reading pane of Outlook Mobile (iOS and Android) to help users identify messages from unverified senders. This feature aligns with existing functionality in Outlook for desktop and web, bringing a consistent experience across platforms. When a message is from a sender we couldn’t verify as safe, users will see a banner in the reading pane warning them to be cautious.

This message is associated with Microsoft 365 Roadmap ID 491471.

[When this will happen:]

General Availability (Worldwide): We will begin rolling out mid-July 2025 and expect to complete by late October 2025 (previously mid-September).

[How this will affect your organization:]

When users receive an email from an unverified sender, they will see a banner in the reading pane explaining why the sender is flagged and warning about potential impersonation. This complements existing safety messages such as:

  • “External sender”
  • “Not on safe senders list”
  • “You don’t often get email from this sender”

This feature is available by default when the unverified signal is received by the service. There are no admin controls to configure or disable this functionality.

[What you need to do to prepare:]

No admin action is required. However, we recommend informing your users about this new visual cue and its purpose. If your organization provides internal training or documentation on email safety, consider updating it to include this new banner.

Learn more: Phishing and suspicious behavior in Outlook

August 19, 2025 at 6:30 PM Updated
Title
Previous
Microsoft Outlook | Outlook Mobile: New unverified sender banner in reading pane
New
(Updated) Microsoft Outlook | Outlook Mobile: New unverified sender banner in reading pane
Summary
Previous
A new unverified sender banner will be introduced in the reading pane of Outlook Mobile (iOS and Android) starting mid-July 2025. This feature helps identify messages from unverified senders, aligning with desktop and web versions. No admin action is required, but user awareness is recommended.
New
Outlook Mobile will display a new banner in the reading pane warning users about emails from unverified senders, aligning with desktop and web versions. Rolling out worldwide from mid-July to mid-September 2025, this feature is automatic with no admin controls. Users should be informed accordingly.
Last Updated Date
Previous
2025-07-10T00:16:59.933Z
New
2025-08-19T16:22:12.490Z
Tags
Previous
Feature update,User impact
New
Updated message,Feature update,User impact
Body Content
Previous

We’re introducing a new visual indicator in the reading pane of Outlook Mobile (iOS and Android) to help users identify messages from unverified senders. This feature aligns with existing functionality in Outlook for desktop and web, bringing a consistent experience across platforms. When a message is from a sender we couldn’t verify as safe, users will see a banner in the reading pane warning them to be cautious.

This message is associated with Microsoft 365 Roadmap ID 491471.

[When this will happen:]

General Availability (Worldwide): We will begin rolling out mid-July 2025 and expect to complete by mid-August 2025.

[How this will affect your organization:]

When users receive an email from an unverified sender, they will see a banner in the reading pane explaining why the sender is flagged and warning about potential impersonation. This complements existing safety messages such as:

  • “External sender”
  • “Not on safe senders list”
  • “You don’t often get email from this sender”

This feature is available by default when the unverified signal is received by the service. There are no admin controls to configure or disable this functionality.

[What you need to do to prepare:]

No admin action is required. However, we recommend informing your users about this new visual cue and its purpose. If your organization provides internal training or documentation on email safety, consider updating it to include this new banner.

Learn more: Phishing and suspicious behavior in Outlook

New

Updated August 19, 2025: We have updated the timeline. Thank you for your patience.

We’re introducing a new visual indicator in the reading pane of Outlook Mobile (iOS and Android) to help users identify messages from unverified senders. This feature aligns with existing functionality in Outlook for desktop and web, bringing a consistent experience across platforms. When a message is from a sender we couldn’t verify as safe, users will see a banner in the reading pane warning them to be cautious.

This message is associated with Microsoft 365 Roadmap ID 491471.

[When this will happen:]

General Availability (Worldwide): We will begin rolling out mid-July 2025 and expect to complete by mid-September 2025 (previously mid-August).

[How this will affect your organization:]

When users receive an email from an unverified sender, they will see a banner in the reading pane explaining why the sender is flagged and warning about potential impersonation. This complements existing safety messages such as:

  • “External sender”
  • “Not on safe senders list”
  • “You don’t often get email from this sender”

This feature is available by default when the unverified signal is received by the service. There are no admin controls to configure or disable this functionality.

[What you need to do to prepare:]

No admin action is required. However, we recommend informing your users about this new visual cue and its purpose. If your organization provides internal training or documentation on email safety, consider updating it to include this new banner.

Learn more: Phishing and suspicious behavior in Outlook

Platforms
Previous
Android
New
Android, iOS

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