Updated September 28, 2026: We have updated the content. Thank you for your patience.
[What and why]
Microsoft Purview Data Lifecycle Management is increasing the maximum auto-expanding archive capacity for eligible Exchange Online archive mailboxes from 1.5 TB to 3 TB. This enhancement helps organizations retain and manage larger volumes of archived email content without requiring manual archive expansion processes or support requests. Eligible mailboxes with auto-expanding archiving enabled will continue to grow automatically as needed.
[Rollout schedule]
- General Availability (Worldwide): Beginning in mid-October 2026 and expected to complete by late October 2026
[Impact on your organization]
Who is affected
- Organizations using Exchange Online archive mailboxes with auto-expanding archiving enabled
- Administrators responsible for Microsoft Purview Data Lifecycle Management and Exchange Online archiving
- Users assigned eligible licenses that support the increased archive capacity
Platforms and services
- Microsoft Purview Data Lifecycle Management
- Exchange Online
- Exchange Online Archiving
What will happen
- Eligible archive mailboxes with auto-expanding archiving enabled can automatically expand beyond the current 1.5 TB limit up to a maximum of 3 TB per mailbox.
- No additional configuration is required for eligible mailboxes that already have auto-expanding archiving enabled.
- No per-GB consumption charge is introduced as part of this change.
- Existing archive content, retention configurations, policies, and holds are unchanged.
- No new administrator workflow, user experience, or user interface is introduced.
- Mailboxes that do not have an eligible license will continue to be limited to 1.5 TB.
Eligible licensing includes:
- Office 365 E5, A5, and G5
- Microsoft 365 E5, A5, and G5
- Microsoft 365 Purview Suite
- Microsoft 365 Purview Suite FLW, EDU, and GOV
- Microsoft Defender + Purview Suite FLW
- Microsoft 365 F5 Compliance
- Microsoft 365 F5 Security + Compliance
- Combination of the eDiscovery & Audit and Insider Risk Management mini suites together with the Information Protection & Governance mini suite
Note:* The maximum auto-expanding archive capacity supported through this feature is 3 TB per mailbox for eligible licenses.
**This feature is available to customers licensed with Microsoft Purview E5 or higher qualifying offerings that include Purview E5 capabilities ex E7.
[Action required and recommendations]
No action is required if eligible mailboxes already have auto-expanding archiving enabled.
We recommend that administrators:
- Review license assignments for users with large archive mailboxes to confirm eligibility.
- Monitor archive mailbox growth using Exchange Online PowerShell.
- Identify mailboxes approaching their applicable archive capacity limits.
- Update internal documentation, retention guidance, and help desk materials to reflect the new 3 TB limit.
- Review licensing and retention strategies for users whose archive mailboxes are not eligible for the expanded capacity.
Learn more
- Enable auto-expanding archiving | Microsoft Learn
- Learn about auto-expanding archiving | Microsoft Learn
[Compliance considerations]
No compliance considerations identified. Review as appropriate for your organization.
