Microsoft 365 shared mailbox reports

Get comprehensive shared mailbox reporting for Microsoft 365 with mailbox permission, activity, storage, and email traffic tracking without any of PowerShell's difficulties.

Shared mailboxes in Microsoft 365 are used by teams to send and receive emails from a common address, such as for support, billing, or information, without requiring a dedicated license. While indispensable for collaboration, they introduce real challenges around access control, activity oversight, and storage governance.

Why you need Microsoft 365 shared mailbox reports

The Microsoft 365 admin center and Exchange admin center offer limited shared mailbox visibility with their Exchange Online reports. They do not provide granular breakdowns of who accessed a shared mailbox, which permissions were granted, how much mail was sent or received, or when a mailbox last saw activity without administrators opening one mailbox at a time. Generating this data through Graph PowerShell scripts demands specialized expertise and a significant time investment.

ManageEngine M365 Manager Plus, the all-in-one Microsoft 365 administration tool, solves this with a dedicated suite of Microsoft 365 shared mailbox reports. Without writing a single line of a PowerShell script, administrators can report and act on all shared mailbox activities in the tenant—all from one centralized reporting console.

M365 Manager Plus provides the following reports:

• Shared Mailboxes
• Shared Mailbox Access
• Send As Shared Mailbox
• Shared Mailbox Activities
• Inactive Shared Mailboxes
• Top Used Shared Mailboxes
• Shared Mailbox Size
• Shared Mailbox Email Activity
• Mails Sent by Shared Mailbox
• Mails Received by Shared Mailbox
• Shared Mailbox Permissions

Shared Mailboxes report

This gives an overview of all the shared mailboxes in the Microsoft 365 environment, with details like the display name, object ID, and alias so you can decide whether to add or delete shared mailboxes.

Shared Mailbox Access report

Audit who has access to each shared mailbox with detailed insights into assigned users and their access rights, such as who accessed the mailbox, the owner of the mailbox, when the mailbox was accessed, and the operation performed.

Send As Shared Mailbox report

Users with the Send As right can send emails from another address and make the message appear to have been sent from the shared mailbox. Track users with Send As permissions to identify who can send emails as the shared mailbox, when they used it, the client IP address, and more in the specified duration.

Shared Mailbox Activities report

Monitor all activities performed within shared mailboxes, including user interactions and access patterns, with details on users who accessed the shared mailbox, the operations performed, the times of the operations, the operation statuses, and more.

Inactive Shared Mailboxes report

Identify shared mailboxes that have not been used for a specified period using the last activity data. Clean up unused mailboxes to optimize resources and reduce clutter.

Top Used Shared Mailboxes report

This ranks shared mailboxes by their email volume, highlighting the most active mailboxes in the tenant over a selected time period. Administrators can quickly identify which shared mailboxes are driving the heaviest traffic, which is useful for planning resources, prioritizing support coverage, and ensuring storage quotas are appropriately configured for high-volume mailboxes.

Shared Mailbox Size report

This displays storage consumption data for every shared mailbox in the tenant, including the total item size, item count, and current usage relative to the assigned storage quota. It gives administrators a clear picture of which mailboxes are approaching or exceeding their limits.

Shared Mailbox Email Activity report

This provides a consolidated view of email traffic across all shared mailboxes over a specified reporting period, with details on emails sent and received and the respective sizes on a per-user, per-day basis.

Mails Sent by Shared Mailbox report

This gives information about emails sent by the shared mailboxes, with details like the email address of the receiver, subject of the email, size of the email, and when it was sent. This helps administrators keep tabs on emails sent from shared mailboxes.

Mails Received by Shared Mailbox report

This gives details about the emails received by the shared mailboxes. It shows the email address of the sender, the subject of the email, the size of the email, when it was received, and more, which helps you keep track of the emails received by the shared mailboxes.

Shared Mailbox Permissions report

The Shared Mailbox Permissions report delivers a comprehensive breakdown of all permissions assigned to each shared mailbox in the tenant. It reports on Full Access, Send As, and Send on Behalf permissions along with the identity of each user or group holding those rights.

Other Exchange Online reports in M365 Manager Plus

M365 Manager Plus includes a broader suite of Exchange Online reports that extend beyond dedicated shared mailbox views. Many of these reports, such as mailbox delegation reports, non-owner mailbox access reports, mailbox forwarding reports, and distribution group reports, also display shared mailbox data alongside other recipient types. All Exchange Online reports in M365 Manager Plus support scheduled report delivery, multi-format exports (CSV, XLSX, PDF, or HTML), and tenant-scoped filtering.

Why choose M365 Manager Plus as your Exchange Online reporting tool?

Managing Exchange Online at scale means keeping tabs on mailbox usage, permissions, mail flow, and compliance—all at once. M365 Manager Plus gives IT teams a single structured view of their Exchange Online environment so they can spend less time pulling data and more time acting on it.

• Unlimited data retention: Microsoft's native audit logs disappear after 180 days. M365 Manager Plus stores report and audit data on your own infrastructure for as long as you need it, so compliance reviews and historical investigations aren't blocked by an arbitrary retention window.
• Scriptless access to advanced data: Some of the most useful Exchange Online attributes are only accessible through PowerShell. M365 Manager Plus provides them through a point-and-click interface with flexible filtering and no scripts to write, test, or maintain.
• Actionable reports: Reports shouldn't be dead ends. With M365 Manager Plus, you can create, modify, or delete mailboxes, distribution groups, and shared mailboxes directly from within a report, keeping your workflow in one place.
• Custom reports: Every environment has different priorities. Build Exchange Online reports around the attributes that matter to your team, ranging from mailbox sizes and inactive users to forwarding rules and permission changes. Then, save and schedule the reports so the same setup is ready whenever you need it.
• Automated scheduling and delivery: Schedule any Exchange Online report to run automatically and send the results straight to the right inboxes on a cadence that works for your team.
• Delegated reporting across tenants: In multi-tenant environments, not every admin needs to see everything. Scope reporting access so each administrator sees precisely what's relevant to their role, without granting broader permissions than necessary.

Other features of M365 Manager Plus

• Exchange Online management: Create, modify, and delete mailboxes, distribution lists, shared mailboxes, and resource mailboxes in bulk with no remote PowerShell sessions required.
• Microsoft 365 reporting: Get over 700 prebuilt and custom reports spanning Entra ID, SharePoint Online, Teams, OneDrive for Business, and more—all accessible from a single dashboard.
• Microsoft 365 management: Handle users, groups, mailboxes, Teams, SharePoint permissions, and license assignments across workloads without jumping between admin portals.
• Microsoft 365 automation: Automate routine tasks like onboarding, offboarding, license provisioning, and group updates using no-code workflows without any extra subscriptions.
• Microsoft 365 auditing: Keep a complete, searchable record of every change across your Microsoft 365 environment, including Exchange Online configuration changes and mailbox access events.
• Microsoft 365 alerting: Stay ahead of issues with real-time alerts on suspicious mailbox access, forwarding rule creation, admin role changes, and policy violations.
• Microsoft 365 administration delegation: Give help desk staff access to specific Exchange Online tasks without handing over full admin rights or control over users outside the staff's scope .