Do Shared Mailboxes Need a License? Microsoft 365 & Google Workspace (2026)
No, a shared mailbox doesn't need its own license in Microsoft 365 or Google Workspace. But there are exceptions. Here's exactly when a license is required and when it isn't.
A shared mailbox is one of the most cost-effective tools in Microsoft 365 and Google Workspace, but licensing rules are frequently misunderstood. This guide covers exactly when a license is required, when it isn't, and what the license doesn't cover.
For a complete overview of what shared mailboxes are and how they work, see our shared mailbox complete guide. For setup instructions, see our shared mailbox in Outlook guide or our Gmail and Google Workspace guide.
Do shared mailboxes need a license in Microsoft 365?
No, a shared mailbox in Microsoft 365 does not require its own license under standard conditions.
What's included for free
- Up to 50GB of storage per shared mailbox
- Access by unlimited licensed users in your organization
- Send As and Send on Behalf permissions
- Access via Outlook desktop, Outlook Web App, and mobile
- Shared calendar and shared contacts
When does a shared mailbox need a license?
Source: Microsoft Learn About shared mailboxes in Microsoft 365
The key rule to remember
The mailbox is free. The users accessing it are not.
Every person who needs access to a shared mailbox must have a licensed Microsoft 365 account of their own. The shared mailbox itself doesn't consume an additional license — but it also doesn't give any user free access to Microsoft 365.
Do shared mailboxes need a license in Google Workspace?
No, Google Workspace doesn't have a native "shared mailbox" concept identical to Microsoft 365, and neither approach requires a separate license.
Option 1 - Gmail delegation:
A Gmail account where one or more users are granted delegate access. Each delegate must have their own Google Workspace license. The delegated account itself doesn't require a separate license, but it does count against your domain's pooled storage.
Option 2 - Google Groups Collaborative Inbox:
A Group email address that multiple members can access and reply from. Members use their existing Workspace accounts, no additional license needed for the Group itself.
Storage consideration
Google Workspace plans include pooled storage per user across the domain. Shared mailboxes (via either method) consume storage from this pool. If your organization is near its storage limit, adding shared mailboxes will accelerate consumption. Check current usage in your Admin Console.
How does shared mailbox licensing compare across platforms?
For shared mailbox rules and automation setup, see our dedicated guide.
How do you set up a shared mailbox without purchasing a license?
In Microsoft 365
You don't need to purchase any additional license to create a shared mailbox, as long as it stays under 50GB and doesn't require archiving or litigation hold.
Steps:
- Go to Microsoft 365 Admin Center (admin.microsoft.com)
- Navigate to Teams & groups → Shared mailboxes
- Click + Add a shared mailbox
- Enter a display name and email address
- Click Save changes → add members
No license purchase required. The shared mailbox is created immediately and is free.
For the complete setup guide including permissions, see our shared mailbox in Outlook guide.
In Google Workspace
Google Workspace has no native shared mailbox feature, but both Gmail delegation and Google Groups Collaborative Inbox are included in every Google Workspace plan at no extra cost.
For the complete setup guide for both options, see our Gmail and Google Workspace shared mailbox guide.
How do you convert a user mailbox to a shared mailbox to save on licensing?
This is one of the most common reasons teams convert to a shared mailbox, when an employee leaves, their mailbox can be converted to a shared mailbox, removing the need for a paid user license while preserving access to the email history.
The process in Microsoft 365:
Step 1: Remove the license from the user account before or during conversion.
Step 2: Go to Microsoft 365 Admin Center → Users → Active users → select the user → Mail tab → click Convert to shared mailbox.
Step 3: Once converted, the mailbox no longer requires a license (up to 50GB). Grant access to the team members who need it.
Important: After conversion, the original user account no longer needs a paid license, this is one of the most effective ways to reduce Microsoft 365 licensing costs when team members leave.
For the complete conversion guide including PowerShell commands, see our how to convert a distribution group to a shared mailbox guide.
How do you migrate a shared mailbox to Microsoft 365?
If you're moving from an on-premises Exchange server to Microsoft 365, shared mailboxes can be migrated using one of four methods depending on your organization's size and infrastructure.
Cutover migration
All mailboxes transferred at once in a single step. Simple to set up but requires downtime. Best for organizations with fewer than 2,000 mailboxes.
Staged migration
Mailboxes migrated in batches over time. Reduces downtime but only works with Exchange 2003 or 2007.
Hybrid migration
It creates coexistence between on-premises Exchange and Microsoft 365. Most flexible but most complex to set up. Best for large enterprises.
IMAP migration
Best for migrating from non-Exchange systems like Gmail. Migrates email only, calendar and contacts must be migrated separately.
Important: After migration, shared mailboxes retain their free status in Microsoft 365 up to 50GB, no additional license required. For licensing details, see the section above.
Once migrated, connect Email Meter to start tracking response times and SLA compliance automatically — start free →
What the license doesn't cover: the hidden limitation
Here's what most guides on shared mailbox licensing don't tell you.
Your shared mailbox is free. But once it's set up and your team starts using it, you have no visibility into how it's actually performing.
Neither Microsoft 365 nor Google Workspace shows you:
- How long your team takes to respond to emails in the shared mailbox
- Which team member is handling the majority of the workload
- How many emails have received no reply in the last 48 hours
- Whether you're meeting your response time SLA targets
- How volume trends over time
Microsoft Viva Insights tracks personal productivity data, but it doesn't monitor shared mailbox performance. Google Workspace Admin shows basic send/receive counts, but no response time data.
For a support@, sales@, or info@ mailbox handling customer or partner communication, this blind spot is significant. You might know your mailbox is free, but you don't know if it's working
For a complete guide on managing your shared mailbox effectively, see our shared mailbox best practices guide.
If you need more than native shared mailbox functionality, see our best shared inbox tools guide.
What are the other limitations of shared mailboxes in Microsoft 365?
Beyond the 50GB storage limit and the analytics blind spot above, shared mailboxes have several technical limitations worth knowing before you set one up.
Email retention policy
Shared mailboxes are subject to your organization's default email retention policy. Emails may be automatically deleted after a set period depending on your retention settings.
No direct login
Users cannot log in directly to a shared mailbox. They must access it through their own user account in Outlook or Outlook on the web. If you enable direct sign-in, a license is required, see the licensing table above.
Automatic forwarding restrictions
Shared mailboxes cannot automatically forward emails to external email addresses by default. This is a security measure to prevent unauthorized data exfiltration.
Maximum concurrent connections
Shared mailboxes have a limit on concurrent connections. If exceeded, users may experience access issues. For large teams, monitor connection usage regularly.
Limited functionality vs user mailboxes
Shared mailboxes don't support some features available in user mailboxes. For a detailed comparison, see our shared mailbox vs user mailbox guide.
How do you check shared mailbox size in Microsoft 365?
To monitor storage before hitting the limit, two options are available.
Via Microsoft 365 Admin Center:
- Go to Exchange Admin Center → Recipients → Shared
- Select the shared mailbox → Mailbox Usage tab
- View current size, warning threshold, and send/receive limits
Via PowerShell:
Shared mailbox vs distribution list vs Microsoft 365 Group: licensing comparison
Teams often confuse these three options. Here's how they differ on licensing and functionality:
For a complete breakdown of when to use a shared mailbox vs a distribution list, see our shared mailbox vs distribution list guide. For a comparison of shared mailbox vs user mailbox, see our shared mailbox vs user mailbox guide.
How do you track shared mailbox performance?
Email Meter connects to your shared mailbox on Google Workspace or Microsoft 365 and provides the performance data that native platforms don't.
Setup takes under 5 minutes. No changes to how your team works in Outlook or Gmail.
For a complete guide on monitoring shared mailbox performance, see our how to monitor a shared mailbox guide.
Start tracking your shared mailbox performance →
Frequently Asked Questions
Does a shared mailboxes need a license in Office 365?
No. A shared mailbox in Microsoft 365 does not require its own license for storage up to 50GB. However, every user who accesses the shared mailbox must have a licensed Microsoft 365 account. A license is also required if the mailbox exceeds 50GB, needs archiving, requires litigation hold, or has direct sign-in enabled.
Does a shared mailboxes need a license in Google Workspace?
No separate license is required for a shared mailbox in Google Workspace. Whether using delegated Gmail access or a Google Groups Collaborative Inbox, members use their existing Workspace accounts. Storage consumption counts against your domain's pooled storage.
Can a shared mailbox be accessed without a license?
No. While the shared mailbox itself doesn't require a license, every user who needs to access it must have a valid license for their own account (Microsoft 365 or Google Workspace). External users cannot access a Microsoft 365 shared mailbox at all.
Does a shared mailbox need a license to send email?
No, sending email from a shared mailbox does not require a separate license. Users with Send As or Full Access permission can send from the shared address using their own licensed account.
Does a shared mailbox need a license to use Send As?
No. Send As permission can be granted to any licensed user, the shared mailbox itself doesn't need its own license for Send As to work.
What happens if a shared mailbox exceeds 50 GB?
When a shared mailbox approaches 50 GB, it will first stop sending email, then eventually stop receiving email. Senders will receive a non-delivery report. To increase the limit to 100 GB, you must assign an Exchange Online Plan 2 license to the shared mailbox.
How do I assign a license to a shared mailbox in Microsoft 365?
Go to Microsoft 365 Admin Center → Users → Active users → find the shared mailbox account → Licenses and apps → assign the appropriate license (Exchange Online Plan 2 for storage over 50GB or archiving). Note: assigning a license is only necessary in the exception scenarios listed above.
Can I convert a user mailbox to a shared mailbox to save on licensing?
Yes, this is one of the most common ways to reduce Microsoft 365 licensing costs. When an employee leaves, you can convert their mailbox to a shared mailbox, remove the paid license from their account, and grant access to other team members who already have their own licenses.
Can I enable direct sign-in to a shared mailbox in Microsoft 365?
By default, Microsoft blocks direct sign-in to shared mailboxes. If you enable sign-in, you must assign an Exchange Online license to the mailbox, otherwise it violates Microsoft's licensing terms.
Are shared mailboxes free in Office 365?
Yes, shared mailboxes up to 50GB are free in Office 365 (now Microsoft 365). There's no additional cost beyond the licenses your users already have. The exceptions are archiving, litigation hold, and mailboxes over 50GB — all of which require an Exchange Online Plan 2 license.
How do I track performance on a shared mailbox?
Microsoft 365 and Google Workspace don't provide native response time or SLA tracking for shared mailboxes. Email Meter connects to your shared mailbox on either platform and tracks response times, workload distribution, and SLA compliance automatically. Start free here.
