Deleted Mailboxes
View and manage soft-deleted mailboxes in Exchange Online. When a user account is deleted or a mailbox license is removed, the mailbox enters a soft-deleted state and can be recovered within the retention period.
Warning: Soft-deleted mailboxes are permanently purged after 30 days. Recover mailboxes within this window to preserve content. Mailboxes on hold are retained as inactive mailboxes instead.
Deleted Mailbox List
| Column | Description |
|---|---|
| Display Name | Original user’s display name |
| Email Address | Primary SMTP address |
| Deleted Date | When the mailbox was deleted |
| Days Remaining | Days until permanent deletion |
| Mailbox Size | Size of the deleted mailbox |
| Deletion Type | User deleted, license removed, or converted |
Soft-Delete vs Hard-Delete
Soft-Deleted
Mailbox is recoverable for 30 days after deletion:
- User account deleted from Azure AD
- Exchange license removed from user
- Mailbox converted to a different type
- Content is fully preserved during retention period
Hard-Deleted (Permanently Removed)
Mailbox content is permanently destroyed:
- 30-day retention period has expired
- Mailbox was explicitly purged by administrator
- Content cannot be recovered
Recovering a Deleted Mailbox
Restore to Original User
If the Azure AD user account still exists (within 30 days of deletion):
- Restore user — Recover the deleted user from Azure AD recycle bin
- Reassign license — Apply an Exchange Online license to the restored user
- Verify — Confirm the mailbox reconnects with all content intact
Restore to New User
If the original user account is permanently deleted:
- Create new user — Create a new Azure AD account
- Connect mailbox — Link the soft-deleted mailbox to the new user
- Verify — Confirm all content is accessible in the new account
Retention Timeline
| Day | Status |
|---|---|
| Day 0 | User deleted or license removed |
| Day 1-30 | Soft-deleted, recoverable |
| Day 30 | Permanently deleted (unless on hold) |
Note: Mailboxes with Litigation Hold or retention policies become inactive mailboxes instead of being permanently deleted.
Best Practices
- Monitor deletions — Review deleted mailboxes weekly to catch accidental deletions early.
- Use holds for compliance — Apply holds before deletion to preserve content as inactive mailboxes.
- Convert to shared first — Consider converting to shared mailbox before removing the user license.
- Export important data — Export critical mailbox content before account deletion.
API Reference
GET /api/exchange/deleted-mailboxes
List soft-deleted mailboxes
GET /api/exchange/deleted-mailboxes/:id
Get deleted mailbox details
POST /api/exchange/deleted-mailboxes/:id/restore
Restore soft-deleted mailbox
DELETE /api/exchange/deleted-mailboxes/:id
Permanently purge deleted mailbox