Introduction
We’re introducing Auto Archiving for Exchange Online to help prevent mail flow disruptions caused by mailboxes reaching their storage quota. This update ensures real-time mailbox health monitoring by automatically moving the oldest items to the archive when mailbox usage exceeds 96% of its quota. This feature addresses customer feedback for proactive mailbox space management and helps maintain business continuity.
When this will happen:
- Public Preview: Rollout began in mid-November 2025 and is expected to complete early December 2025
- Worldwide rollout: Rollout begins in early January 2026 and is expected to complete late January 2026
How this affects your organization:
Who is affected: Admins managing Exchange Online mailboxes with provisioned archive mailboxes.
What will happen:
- When a primary mailbox exceeds 96% of its quota, Managed Folder Assistant will automatically archive the oldest items until usage drops below the threshold.
- Applies to both IPM folders and Recoverable Items folders.
- Honors Never Move to Archive tags.
- Enabled by default for all tenants.
- Archive mailbox must be provisioned and have available space for auto-archiving to occur.
What you can do to prepare:
Learn more:
Compliance considerations:
No compliance considerations identified, review as appropriate for your organization.