Distribution List vs. Shared Mailbox: Which Should You Use?
- Brandon Alsup
- Jun 1
- 8 min read
Updated: Aug 21
Use a distribution list when one email needs to reach several people's individual inboxes. Use a shared mailbox when several people need to monitor and respond from one common inbox.
A licensed user mailbox is different again: it normally belongs to one real person who signs in with their own account.
For addresses such as support@, billing@, info@, sales@, or reception@, a shared mailbox is usually the better choice if multiple employees need to work with incoming messages.
There are exceptions, especially when storage, security, archiving, litigation hold, or compliance requirements enter the picture.
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We commonly get a request for an email address like info@, billing@, support@, hr@, or reception@, which may seem simple. But behind that address are important questions:
Who receives the messages?
Who can send from it?
Who can log in?
Can we tell who took action?
Does it need multi-factor authentication, archiving, litigation hold, or compliance controls?
Are there compliance (HIPAA or CMMC) considerations?
In Microsoft 365, the most common options are a distribution list, a shared mailbox, or a licensed mailbox. Each has a place. The mistake is treating them as interchangeable.
Quick Comparison: Which Email Setup Is Licensed?
Setup | Is the address itself licensed? | Can people send from it? | Can people log into it directly? | Best for | Watch-outs |
Distribution List | No | Not usually as the list itself (but possible) | No | Sending one email to multiple people | No shared inbox, no mailbox storage, no central sent history |
Shared Mailbox | Usually no, if under standard limits | Yes, with Send As or Send on Behalf permissions | Should not be used for direct login | Team inboxes like support, billing, sales, reception | Requires careful permissions; users accessing it need licensed accounts |
Licensed User Mailbox | Yes | Yes | Yes, by that named user | A real employee’s mailbox | Should not be shared by multiple people |
Licensed Shared Mailbox | Yes, when needed | Yes, with delegated permissions | Still generally accessed through user delegation | Larger mailboxes (50gb vs 100gb), archiving, litigation hold, compliance needs | Adds cost but may be necessary for retention, hold, or storage |
The simplest distinction is:
A distribution list distributes email. A shared mailbox stores email for a team to work on together.
That difference sounds small, but it can create very different workflows.
What Is a Distribution List?
A distribution list—Microsoft also calls these distribution groups—is essentially an email address connected to a list of recipients.
For example, sending a message to: leadership@company.com might send a copy to:
the CEO
the CFO
the operations director
the HR director
Each person receives the message in their own mailbox.
The distribution list itself does not have a traditional inbox where the group opens and manages messages together.
Microsoft describes distribution groups as a way to send email to a group of people without entering every recipient individually.
Distribution lists work especially well for addresses such as:
They're particularly useful when the purpose is broadcasting information.
Does a distribution list have a mailbox?
No. A distribution list doesn't function as a normal mailbox with its own inbox and stored message history.
Messages sent to the list are distributed to the members' individual mailboxes.
That is one of the biggest differences between a distribution list and a shared mailbox.
Can you send from a distribution list?
Yes, Microsoft 365 can be configured to allow authorized users to Send As a distribution list.
That can be useful for announcements that should appear to come from an address such as leadership@company.com rather than from one employee.
But it still does not turn the distribution list into a shared inbox.
Why Distribution Lists Get Misused
Problems usually begin when a business takes an address that requires action and turns it into a distribution list.
Consider: support@company.com
A customer sends an email.
If support@ is a distribution list, five employees may each receive their own copy.
Now what happens?
One person may respond.
Two people may respond.
Or everyone may assume somebody else handled it.
There is no single inbox everyone is working from, and there is no simple shared view of the conversation.
That's why I generally prefer distribution lists for communication to a group, not work assigned to a group.
What Is a Shared Mailbox?
A shared mailbox is an actual mailbox that multiple authorized users can access.
Examples include:
Instead of five separate copies of an incoming message being scattered across five employee inboxes, the team has one common mailbox.
Users can be given different Microsoft 365 permissions, including:
Full Access — allows the user to open and manage the mailbox.
Send As — messages appear to come directly from the shared mailbox.
Send on Behalf — messages identify the employee as sending on behalf of the mailbox.
Microsoft specifically describes shared mailboxes as useful when multiple people need access to a common address such as an information or support mailbox.
Does a Shared Mailbox Need a License?
Usually not.
This question is already bringing this article Google visibility, so the distinction is worth making very clear.
Microsoft currently allows a shared mailbox to operate without its own separate license under normal circumstances, provided the people accessing it have appropriate Exchange Online licensing.
An unlicensed shared mailbox is generally limited to 50 GB.
A separate license becomes necessary in certain situations involving additional storage or advanced functionality.
When Does a Shared Mailbox Need a License?
Common examples include:
Requirement | Licensing Consideration |
More than 50 GB of mailbox storage | Exchange Online Plan 2 may be required |
In-place archiving | Additional licensing may be required |
Litigation hold | Appropriate Exchange licensing is required |
Advanced retention/eDiscovery/security capabilities | License requirements depend on the feature |
Other Microsoft Purview capabilities | Depends on the compliance feature being used |
Microsoft's current documentation specifically identifies more than 50 GB of shared-mailbox storage, in-place archiving, and litigation hold as scenarios requiring Exchange Online Plan 2 or appropriate additional licensing.
That leads to an important point:
"Shared mailbox" does not necessarily mean "free mailbox."
For a basic team inbox, there may be no additional mailbox license.
For an organization with significant storage, compliance, archiving, retention, or investigation requirements, there may be.
For a broader look at the differences between Microsoft licensing levels, see our guide to Microsoft license types and what businesses actually need.
Don't Share a Password for a Shared Mailbox
This is one of the mistakes we still encounter.
A business creates: billing@company.com and then gives five employees the username and password.
That's not how a Microsoft 365 shared mailbox should normally be used.
Microsoft blocks sign-in to newly created shared mailboxes by default. Instead, employees should access the mailbox through their own individual Microsoft 365 accounts using delegated permissions.
That gives the organization much better control over:
MFA
Conditional Access
user permissions
account removal
auditing
security policies
If an employee leaves, their access can simply be removed.
Nobody needs to change a shared password that six other people know.
When Should You Use a Licensed User Mailbox?
A licensed user mailbox normally belongs to a real individual.
Examples:
That person signs in using their own identity and typically has their own Microsoft 365 license.
What I would avoid is creating something like: frontdesk@company.com as a normal licensed user account and then handing the same password to three receptionists.
Paying for a license doesn't solve the underlying security problem.
If several people are supposed to work from the same operational address, a properly configured shared mailbox is normally cleaner.
Distribution List vs. Shared Mailbox: Which Should You Choose?
Here's the practical test I use.
Use a distribution list when:
You want one message delivered to several people.
Examples:
company announcements
leadership communications
department updates
internal notifications
There is usually no need for a team to manage a conversation together.
Use a shared mailbox when:
You want several people working from one email address.
Examples:
support
billing
reception
sales inquiries
scheduling
general information requests
People need to see the same messages and respond from the same organizational identity.
Use a licensed user mailbox when:
The mailbox belongs to one actual person who needs to log in and use Microsoft 365 as themselves.
License a shared mailbox when:
The mailbox needs capabilities beyond the standard unlicensed shared-mailbox limits, such as additional storage, certain archiving capabilities, litigation hold, or advanced compliance features.
Shared mailbox licensing is only one small piece of Microsoft's licensing system. For the bigger picture, see our guide to Microsoft 365 license types and what businesses actually need.
One More Question: Has the Shared Mailbox Become a Help Desk?
There's another distinction businesses often discover later.
A shared mailbox lets several people work from one inbox, but it isn't automatically a ticketing system.
If support@company.com receives 20 relatively simple messages each week, a shared mailbox may work perfectly well.
If it receives hundreds of requests and you need:
ticket ownership
assignment
escalation
response-time tracking
service-level reporting
automation
customer history
then the question may no longer be distribution list versus shared mailbox.
You may need a dedicated help desk or shared-inbox workflow system.
The technology should match the amount of coordination the team actually needs.
Security and Compliance Change the Decision
For regulated organizations, we look beyond whether email simply works.
Healthcare organizations, government entities, financial organizations, defense contractors, and other regulated businesses may need to consider:
MFA
delegated access
auditability
retention
archiving
eDiscovery
DLP
encryption
litigation hold
Microsoft Purview capabilities
A mailbox used for patient communication, HR information, financial information, or CMMC-controlled environments may therefore require a different configuration than a general info@ address.
For CMMC environments in particular, licensing decisions can affect which security and compliance capabilities are available. We've covered that separately in our guide to choosing Microsoft licenses for CMMC readiness.
You can also read our overview of Microsoft 365 email security.
Frequently Asked Questions
What is the main difference between a distribution list and a shared mailbox?
A distribution list sends copies of an email to multiple individual mailboxes. A shared mailbox is one central mailbox that multiple authorized users can access and work from together.
Does a shared mailbox need a Microsoft 365 license?
Not usually under Microsoft's standard shared-mailbox limits. The users accessing the mailbox need appropriate licenses, while the shared mailbox itself can normally remain unlicensed up to 50 GB. Additional storage, archiving, litigation hold, or advanced features can require licensing.
Does a distribution list have an inbox?
No. A distribution list distributes messages to its members. It does not provide a normal shared inbox where the group stores and manages email together.
Is a shared mailbox better than a distribution list?
Neither is universally better because they solve different problems. A distribution list is better for broadcasting messages. A shared mailbox is usually better when multiple people need to monitor and respond to messages from one address.
Can users send email from a distribution list?
Yes, an administrator can grant appropriate users Send As permission for a Microsoft 365 distribution list. The list still does not function as a shared mailbox.
Should support@ be a distribution list or shared mailbox?
For most businesses, a shared mailbox is the better choice because multiple employees can work from the same mailbox and respond using the support address. A distribution list is generally better when messages only need to be distributed rather than managed collectively.
The Bottom Line
The easiest way to make the decision is to ask what happens after the email arrives.
If the message simply needs to reach several people, a distribution list is probably enough.
If several people need to work on the message and respond from one common business address, use a shared mailbox.
If the mailbox belongs to one actual employee, use a licensed user mailbox.
And if a shared mailbox needs larger storage, archiving, litigation hold, or advanced compliance capabilities, determine whether the mailbox itself needs additional Microsoft licensing.
We've helped organizations ranging from healthcare businesses to municipalities work through these exact Microsoft 365 decisions. The technical setup is usually straightforward once the business workflow, security requirements, and ownership are clear.
For help reviewing your Microsoft 365 environment, see our Microsoft services.
Disclaimer
The information contained in this communication is intended for limited use for informational purposes only. It is not considered professional advice, and instead, is general information that may or may not apply to specific situations. Each case is unique and should be evaluated on its own by a professional qualified to provide advice specifically intended to protect your individual situation. Kosh is not liable for improper use of this information.
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