How to Add a Shared Mailbox in Outlook on the Web

To add a shared mailbox in Outlook on the web, sign in with your work or school account, right-click Folders in the folder pane, choose Add shared folder or mailbox, enter the mailbox name or email address, and select Add. Your organization must first grant your account access; adding the mailbox in Outlook does not create permissions.

What a shared mailbox is and how it works

A shared mailbox is an organizational email address that several approved people can use, such as support@contoso.com or invoices@contoso.com. Unlike a personal mailbox, it is meant for a group to read and respond to messages using a common address. The mailbox can also contain shared folders such as Inbox, Sent Items, and Calendar, depending on how it is configured.

Access is assigned to individual users by an administrator, typically through the organization’s Microsoft 365 or Exchange administration tools. A shared mailbox is not normally signed into directly with its own password. Instead, you sign in to your own account and open the mailbox from there. This helps the organization manage access when someone joins or leaves the team.

Outlook on the web is the browser version of Outlook, commonly reached through Microsoft 365 or Outlook on the web at your organization’s address. Menu labels and the folder-pane layout can vary slightly as Microsoft updates the interface, but the shared-mailbox option is usually in the folder pane’s context menu.

Check access before adding the mailbox

If the mailbox is not already visible, ask your Microsoft 365 or Exchange administrator to confirm that your account has permission. For reading and managing mail, the key permission is generally Full Access. Sending from the shared address is a separate capability: the administrator may also need to grant Send As or Send on behalf.

These permissions do different jobs. Full Access lets you open and work with the mailbox, but does not by itself authorize you to send mail as that address. Send As makes a message appear to come directly from the shared address. Send on behalf shows that you sent the message on behalf of the shared mailbox. Your organization decides which permissions are appropriate.

Confirm the exact mailbox email address, especially if your organization has similar names or aliases.
Ask whether access has been granted to your own account, not just to a team or another colleague.
If you need to reply from the shared address, ask specifically about Send As or Send on behalf permission.
Allow time for newly assigned access to become available; it may not appear immediately.

Shared mailboxes are generally managed by an organization, rather than created by an individual from Outlook on the web. If the address does not exist yet, an administrator may need to create it before anyone can open it.

Steps to add a shared mailbox in Outlook on the web

Open Outlook on the web and sign in using the account that has been granted access.
In the left folder pane, find Folders. If the pane is collapsed, expand it using the navigation or folder-pane control.
Right-click Folders. On a touch device or in an interface without a right-click, use the available context-menu control for the folder pane.
Choose Add shared folder or mailbox. If that exact wording is not shown, check the folder pane’s menu for an option to add a shared folder or mailbox.
Enter the shared mailbox’s email address or name, select the matching result if prompted, and choose Add.

The mailbox should then appear in the folder list, usually as a separate mailbox entry that you can expand to see its folders. Select its Inbox to read messages. If Outlook reports that it cannot find the mailbox, first verify the address and permissions rather than repeatedly adding different spellings of the name.

Some organizations’ Outlook on the web layouts provide another route, such as an option to open another mailbox from the account or profile menu. That can be useful for opening a mailbox temporarily, but the folder-pane method is the straightforward way to add it to the folder list when available.

Find the mailbox and work with its folders

After adding it, look in the folder pane for the mailbox’s display name or email address. Select the arrow beside the entry to expand or collapse its folders. The shared Inbox is separate from your own Inbox, so check which mailbox is selected before reading, moving, or deleting a message. A message moved into the shared mailbox’s folders is handled there, not in your personal mailbox.

If the shared mailbox has a large folder tree, expand only the folders you need. You can use Outlook’s search, but check the search scope: a search may apply to the current folder or mailbox rather than every mailbox you can access. Select the shared mailbox or one of its folders first when you want to limit a search to that location. Search behavior and available filters can vary with the Outlook interface and organization settings.

When several people work from the same Inbox, agree on a simple process for ownership. For example, team members might categorize messages that are being handled, move completed requests to a designated folder, or use flags consistently. Outlook does not automatically prevent two people from replying to the same message, so a shared workflow can reduce duplicate responses.

Send a message from the shared address

To send from the shared mailbox, create a new message and check the sender shown in the From field. If you do not see that field, use the compose window’s options to show it; the location can differ slightly across Outlook layouts. Select From, choose the shared address if it is listed, or select Other email address and enter the address. Then write and send the message as usual.

If Outlook displays a permission error, or the message is sent from your personal address instead, you may have Full Access without permission to send as the mailbox. Ask your administrator to check Send As or Send on behalf access. Do not assume that being able to read the shared Inbox means you can send from its address.

Where a message appears after sending depends partly on mailbox configuration. Organizations can configure copies of messages sent as or on behalf of a shared mailbox to be saved in the shared mailbox’s Sent Items. If a sent message appears only in your personal Sent Items, ask the administrator whether shared sent-item copies are enabled. This setting matters when colleagues need to see what the group has already answered.

Before sending a sensitive or customer-facing reply, verify the From address, recipients, and any attachments. A message sent from a shared address represents the organization or team, and the shared mailbox may be monitored or managed under workplace policies.

Automatic appearance, manual adding, and permissions

In some cases, a mailbox with the right access appears in Outlook automatically. This can happen when the administrator assigns Full Access in a way that supports automatic mailbox mapping. If it has not appeared, manually adding it through the folder pane is a reasonable next step, provided you have permission. The mailbox may take some time to show after an administrator changes access, and signing out and back in or refreshing Outlook can help after that change has had time to apply.

Manually adding a mailbox is a way to make it visible in your Outlook view; it does not increase your access level. It cannot grant Full Access, change who is allowed to use the mailbox, or enable sending. If the add option is unavailable or the mailbox cannot be resolved, your organization may have a different Outlook configuration, or the account may not yet have the required access.

Administrators also decide which users can access a mailbox and whether they can read, manage, or send messages. Avoid asking a colleague to share their password or trying to sign in as the mailbox itself. Use your own account and request the specific permissions required for your role.

Common problems and practical fixes

The mailbox does not appear after adding it: Refresh Outlook, expand the folder pane, and check whether the entry is lower in the folder list. Confirm the address and ask the administrator whether permission has been assigned to your account.
Outlook says the mailbox cannot be found: Check for a typo and use the primary email address rather than a display name that may be shared by several people. If the address is correct, the mailbox may not exist or may not be available to your account.
You can open the mailbox but cannot send from it: This commonly means you have access to read and manage mail but lack Send As or Send on behalf permission. Ask the administrator which sending method your team uses.
The shared address is missing from the From list: Show the From field in the compose window and try selecting the address through Other email address. If sending is still denied, request the appropriate send permission.
Changes take time to appear: Newly granted access may take a while to become available. Refresh or sign out and back in after allowing time for the change to propagate. If it remains unavailable, have the administrator verify the assignment.
The folder pane or menu looks different: Outlook’s web interface changes over time and can differ by account or organization. Expand the navigation pane and look for the folder context menu; if the add command is absent, ask your support team for the steps specific to your organization.

When reporting a problem to support, include the mailbox address, your own work account, what you were trying to do, and the exact error message. Do not include a password or forward private mailbox content unless your organization’s process requires it.

Security and good shared-mailbox habits

Use only the mailbox access your work requires, and tell the administrator when you no longer need it. Shared mailboxes can contain personal, customer, financial, or otherwise confidential information. Follow your organization’s retention, privacy, and data-handling rules rather than treating a shared Inbox as an informal storage space.

Because users access the mailbox through their own accounts, protect your account with the security measures required by your organization, such as multifactor authentication. Do not share sign-in credentials, and be cautious about leaving Outlook open on a public or shared computer. Sign out when appropriate and follow workplace guidance for devices and browser sessions.

Teams should also agree how to handle messages that are urgent, sensitive, or already being answered. Clear ownership and consistent use of folders or categories help reduce duplicate work. If a message requires a record of who sent it, remember that Send As and Send on behalf display different sender information; choose the organization-approved option.

Frequently Asked Questions

Why can’t I add a shared mailbox in Outlook on the web?
Most often, your account has not been granted the required access, the mailbox address is incorrect, or the interface is using a different menu layout. Confirm the address and ask your Microsoft 365 or Exchange administrator to verify your permissions.

Do I need a separate password for a shared mailbox?
Usually not. You open it while signed in to your own work or school account. Avoid signing in as the shared mailbox or asking someone to provide its credentials; access should be assigned to your account.

Can I send email from a shared mailbox?
Yes, if your organization has granted Send As or Send on behalf permission. Full Access alone generally allows you to work in the mailbox but does not authorize sending from its address.

Will the shared mailbox appear automatically?
It may, depending on how the administrator assigned access and how Outlook is configured. If it does not appear, try adding it from the folder pane. Manual addition makes it visible but does not grant permissions.

Can I add a shared mailbox from Outlook on the web on my phone?
The web interface may be harder to use on a small screen, and context-menu actions vary by device. If you cannot access the folder menu, try Outlook in a desktop browser or ask your organization whether its mobile Outlook app supports the mailbox workflow you need.

What should I do if replies do not show in the shared Sent Items?
Check your personal Sent Items first, then ask the administrator whether copies of messages sent as or on behalf of the shared mailbox are configured to be saved in its Sent Items folder. This is an administrative mailbox setting, not something adding the mailbox necessarily changes.

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