What Are Shared Mailboxes in Microsoft 365?

Shared mailboxes are one of the most useful features in Microsoft 365 for businesses that need teams to manage emails from a central address.

Instead of emails going to one person’s inbox, a shared mailbox allows multiple authorised users to access the same mailbox. This is ideal for addresses such as:

• info@yourcompany.co.uk
• sales@yourcompany.co.uk
• support@yourcompany.co.uk
• accounts@yourcompany.co.uk
• enquiries@yourcompany.co.uk

For many businesses, shared mailboxes help improve communication, reduce missed emails, and make sure customer enquiries are visible to the right people.

How Does a Shared Mailbox Work?

A shared mailbox is a mailbox that multiple users can access from their own Microsoft 365 accounts.

For example, if your business has an email address such as support@yourcompany.co.uk, you may want several members of the team to read and respond to those emails.

Rather than giving everyone the same password, Microsoft 365 allows each user to sign in with their own account and then access the shared mailbox based on permissions.

This is much safer and easier to manage.

It means users do not need to share login details, and the business can control who has access.

What Are Shared Mailboxes Used For?

Shared mailboxes are commonly used for team-based email addresses.

For example, a sales team may use sales@ so several people can see new enquiries. An accounts team may use accounts@ to manage invoices and payment queries. A support team may use support@ to respond to customer issues.

They are also useful when a business wants continuity. If one person is on holiday, off sick, or leaves the company, other authorised users can still access the shared mailbox and continue dealing with messages.

This helps prevent important emails being missed or stuck in one person’s inbox.

Common Examples of Shared Mailboxes

Shared mailboxes are often used for:

• General enquiries
• Sales enquiries
• Customer support
• Accounts and finance
• HR
• Bookings
• Projects
• Reception or admin teams
• Departmental mailboxes
• Former employee mailboxes that need to be retained temporarily

They are especially useful for small businesses where several team members may need to help manage the same type of communication.

Do Shared Mailboxes Need a Licence?

In many cases, a shared mailbox does not need its own separate Microsoft 365 licence, provided it is used within Microsoft’s limits and users access it through their own licensed accounts.

This can make shared mailboxes a cost-effective way to manage team email addresses.

However, licensing can depend on how the mailbox is used, its size, and whether additional features are required. For example, if a shared mailbox needs more storage, archiving, or direct sign-in, different licensing requirements may apply.

This is why it is important to set shared mailboxes up correctly rather than treating them like normal user accounts.

Shared Mailbox Permissions

Microsoft 365 uses permissions to control what users can do with a shared mailbox.

The main permissions are:

Full Access

This allows a user to open the shared mailbox, view emails, create items, delete messages, and manage the mailbox contents.

Send As

This allows a user to send an email that appears to come directly from the shared mailbox. For example, the recipient sees the email as coming from support@yourcompany.co.uk.

Send on Behalf

This allows a user to send an email on behalf of the shared mailbox. The recipient may see something like “Carl on behalf of Support.”

These permissions should be applied carefully so users only have the access they actually need.

Why Shared Mailboxes Are Better Than Shared Passwords

Some businesses still use shared login details for team mailboxes.

For example, several people may know the password for info@ or accounts@.

This is not recommended.

Shared passwords create several problems:

• It is harder to know who accessed the mailbox
• Passwords are often not changed when staff leave
• Multi-factor authentication becomes difficult to manage
• Access cannot be controlled properly per user
• There is a higher risk of unauthorised access
• It creates security and compliance issues

A properly configured shared mailbox avoids these problems because every user signs in with their own Microsoft 365 account.

If someone leaves the business, their access can simply be removed.

Shared Mailboxes and Security

Shared mailboxes should still be managed securely.

Even though users access them through their own accounts, businesses should regularly review who has access. Old permissions should be removed, especially when staff change roles or leave the company.

It is also important to make sure users have multi-factor authentication enabled on their own accounts.

Businesses should also consider whether the mailbox contains sensitive information, such as financial details, HR records, customer data, or confidential documents.

If it does, access should be limited to the right people only.

Shared Mailboxes and Sent Items

One area businesses often overlook is sent items.

When users send emails from a shared mailbox, you may want those emails saved in the shared mailbox’s Sent Items folder, not just the individual user’s sent folder.

This helps the whole team see what has already been sent and avoids duplicated replies.

This setting can be configured in Microsoft 365, but it is not always set up correctly by default.

Shared Mailboxes Are Not a Replacement for a Ticketing System

Shared mailboxes are useful, but they are not always the best solution for every situation.

For example, if your business receives a high number of support requests, a shared mailbox may become difficult to manage.

Emails can be missed, duplicated, or handled by more than one person at the same time.

In these cases, a proper ticketing system may be better. A ticketing system can assign ownership, track response times, record notes, report on workload, and make sure nothing falls through the cracks.

Shared mailboxes are excellent for simple team email management, but they should not always be treated as a full helpdesk solution.

When Should a Business Use a Shared Mailbox?

A shared mailbox is a good option when multiple people need to access and respond to emails from one business address.

It is particularly useful for smaller teams, departmental inboxes, and general enquiries.

You should consider using a shared mailbox when:

• More than one person needs to monitor an email address
• You want to avoid shared passwords
• You need continuity when staff are away
• You want a central place for team emails
• You need users to send from a common business address
• You want better control over mailbox access

Setting Shared Mailboxes Up Properly

Shared mailboxes are simple in principle, but they still need to be configured correctly.

This includes setting the right permissions, checking sent item behaviour, reviewing access regularly, applying appropriate security controls, and making sure the mailbox is used in the right way.

For businesses using Microsoft 365, shared mailboxes can be a practical and cost-effective way to manage team communication.

How Hamilton Group Can Help

At Hamilton Group, we help businesses get the most out of Microsoft 365.

We can create and configure shared mailboxes, set the correct permissions, remove shared passwords, improve mailbox security, review existing access, and make sure your Microsoft 365 environment is set up properly.

We can also advise when a shared mailbox is enough and when your business may benefit from a ticketing system or more structured process.

If you would like help setting up or reviewing shared mailboxes in Microsoft 365, speak to Hamilton Group.

Call us on 0330 0430069 or book an appointment with one of our experts.