Add a Shared Mailbox in Outlook App: Setup Steps

To add a shared mailbox in Outlook, first ask your Microsoft 365 or Exchange administrator to grant your account access, then add the mailbox in Outlook for Windows, Mac, or mobile. A shared mailbox lets an approved team read and manage mail sent to a common address; it is not a separate account that you sign into with its own password.

What You’ll Need

Permission to use the mailbox. Ask your organization’s Microsoft 365 or Exchange administrator to grant you access. Full Access lets you open and manage the mailbox. Sending from its address generally also requires Send As or Send on behalf permission.
The shared mailbox address. This is usually a team address such as support@company.com. Use the address, not just the mailbox display name, when searching or entering it.
Your work or school account in Outlook. The account that has been granted permission should already be signed in. Shared mailboxes are normally part of a Microsoft Exchange or Microsoft 365 organization, not personal Outlook.com mailboxes.
A current Outlook app and an internet connection. Menu names can vary slightly between classic Outlook, new Outlook, Mac, and mobile versions. Update Outlook if a described option is missing.

Step-by-Step

Confirm access before changing Outlook. Contact the mailbox owner or IT team and provide the exact shared address. Ask for Full Access if you need to read, organize, or reply to its messages. If you must send mail that appears to come directly from the shared address, ask for Send As as well. Send on behalf is a different permission and displays your name as sending on behalf of the mailbox. Permission changes can take time to reach Outlook, so note when access was granted.
Open Outlook and check which version you have. On Windows, classic Outlook has a File tab on the ribbon; new Outlook usually has a Settings gear and a simplified interface. If you are unsure, look for a Try the new Outlook switch or check the app name in Windows. Use the matching method below rather than trying to follow both sets of menus. On a Mac, open Outlook and use the Mac-specific instructions in step 5.
In new Outlook for Windows, add the mailbox from the folder pane. Go to Mail and locate the folder pane on the left. Right-click your work or school account name, then choose Add shared folder or mailbox. If the pane already has a Shared with me section, you may be able to right-click that section and choose the same option. Enter the shared mailbox’s email address, select the matching result, and choose Add. The mailbox should appear in the folder pane. If Outlook offers a matching suggestion while you type, verify the address before selecting it.
In classic Outlook for Windows, add it in account settings. Select File > Account Settings > Account Settings. On the Email tab, select your Microsoft 365 or Exchange account, then choose Change. Select More Settings, open the Advanced tab, and choose Add under Open these additional mailboxes. Type the shared mailbox address or name, select the correct result, and choose OK. Choose Next and Finish if those buttons appear, then close the account settings windows and restart Outlook. The mailbox should show in the folder list below your main mailbox.
On Outlook for Mac, add it as a delegated mailbox. Open Outlook > Settings > Accounts, select the work or school account that has access, and open Delegation and Sharing. Select the Shared With Me tab, choose the plus button, and search for or enter the shared mailbox address. Select the correct mailbox and add it. Depending on your Outlook for Mac version, the setting may be under Tools > Accounts or the wording may differ. If you cannot find Delegation and Sharing, update Outlook or ask your administrator which Mac version your organization supports.
On Outlook for iOS or Android, add it from the account menu. Open Outlook, tap your profile picture or account icon, then choose the add-account control. Select Add a Shared Mailbox if it appears, choose the work or school account that has permission, and enter the shared mailbox address. Follow any prompts to finish. Do not choose the option to add a regular email account and enter a made-up password; a shared mailbox normally uses your existing organizational sign-in and permission.
Wait for the mailbox to load and check its folders. Expand the shared mailbox in the folder pane or account list. Look for Inbox, Sent Items, and any team folders. If it does not show immediately, allow time for permissions to propagate, then close and reopen Outlook. In some organizations, Full Access is configured to add the mailbox automatically, so it may appear without manual setup. Avoid adding a second copy if it is already listed.
Test reading and replying. Open a message in the shared Inbox and confirm you can read it. When replying, check the From field before sending. If you do not see it, choose the option to show the From field if necessary, then select the shared address. Send a brief test only if appropriate for your organization. If Outlook refuses to send from that address, the mailbox may be added correctly but your account may still lack Send As or Send on behalf permission.
Use the mailbox deliberately in daily work. Select the shared Inbox before creating a message if you want the message associated with the shared mailbox. Confirm the From address and where the message is saved after sending. Shared mailbox settings can be configured so sent messages are stored in the shared Sent Items folder, but this behavior depends on your organization’s Exchange configuration. Ask IT if you need team members to see the sent replies in one place.

Common Mistakes

Trying to sign in with the shared address. Most shared mailboxes do not have a separate password for users. Sign in with your own work or school account, which must have permission to access the mailbox.
Assuming access to read means access to send. Full Access and sending permissions are separate. If you can open messages but cannot send as the mailbox, ask IT to check Send As or Send on behalf rights.
Choosing the wrong Outlook instructions. Classic Outlook’s File and Advanced settings are not the same as new Outlook’s folder-pane menu. Identify the app version first; do not look for a classic Outlook File tab in new Outlook.
Adding a mailbox you already have. Some administrators enable automatic mapping, so the mailbox appears on its own. Check the folder pane and account list before adding it manually, since duplicate entries can be confusing.
Expecting a permission change to work instantly. Exchange changes may need time to propagate. Repeatedly adding and removing the mailbox is unlikely to speed that process up.

Tips

Verify the address and display name. Organizations sometimes have several shared mailboxes with similar names. Confirm the full email address with the mailbox owner before adding or sending from one.
Check the From field on every new message. Outlook may default to your personal work address even when you are viewing the shared Inbox. Choose the shared address explicitly when needed, especially for a new message rather than a reply.
Use the shared mailbox for team mail, not personal storage. Keep messages in the appropriate shared folders and follow your organization’s retention and privacy rules. Do not move sensitive mail to a personal mailbox to work around a permission issue.
Keep Outlook updated and allow for syncing. A mailbox can take a short time to populate, particularly on a phone or after a permission change. A stable connection and a current app help distinguish a sync delay from an access problem.
Ask about sent-message handling. If teammates need to see replies, ask IT whether messages sent as the mailbox are saved in its Sent Items folder. The sender’s view and the team’s shared view may differ if that setting is not enabled.

Troubleshooting

The mailbox does not appear: First verify that your own account has Full Access to the exact mailbox address. Check the folder pane for a Shared with me section or an automatically added mailbox, then restart Outlook. In new Outlook, try the Add shared folder or mailbox option again and confirm you selected the correct search result. In classic Outlook, revisit the Advanced tab in account settings. If the address is not found, or access was granted recently, contact IT to confirm the mailbox exists and allow time for permissions to update.

You can see the mailbox but cannot open a folder or message: Confirm that Full Access was granted to the account currently signed in to Outlook. If you have multiple work accounts, make sure you added the mailbox under the account with permission. Sign out and back in only if your organization permits it; do not remove your primary account or delete organizational data as a first step. Report any access-denied message to the mailbox owner or help desk.

You can read mail but cannot send from the shared address: This usually means the mailbox is available but your sending permission is missing or has not taken effect. Ask your administrator to check Send As or Send on behalf rights. Also inspect the From field: if it is hidden, display it and select the shared address. If Outlook reports that you do not have permission, do not keep retrying; send from your own address only if that is acceptable for the message.

Mail or folders are missing, or the app behaves differently: Refresh the mailbox, check your connection, and compare Outlook on the web if your organization allows it. If the mailbox works on the web but not in the app, update Outlook, restart it, and report the app version and device to IT. On mobile, confirm you added a shared mailbox rather than a second personal account. Avoid deleting cached files or rebuilding a profile unless your support team recommends it, as those steps can affect other accounts.

Frequently Asked Questions

Do I need a password for a shared mailbox?
No, in most organizations you access it through your own Microsoft 365 or Exchange account. The administrator grants your account permission; do not try to guess or request a separate mailbox password unless IT specifically instructs you to use a different setup.

Can I add a shared mailbox in Outlook without administrator help?
You can usually add it yourself after access has been granted. If Outlook cannot find it or reports that you lack permission, the mailbox owner or administrator needs to check your access and, if relevant, sending rights.

Why can I read shared mail but not send as the mailbox?
Reading and sending are controlled by different permissions. Ask for Send As if messages should appear to come directly from the shared address, or Send on behalf if your organization wants your identity shown alongside it.

Will the shared mailbox appear automatically?
It may. Some Exchange configurations automatically map mailboxes when Full Access is granted, but this depends on organizational settings and can take time. Check Outlook’s folder pane before adding it manually.

Can I add a shared mailbox to Outlook on my phone?
Yes, Outlook for iOS and Android supports shared mailboxes for accounts with the necessary access. Use the Add a Shared Mailbox option from the account menu, where available, and select the authorized work or school account.

Will everyone see messages I send from the shared mailbox?
Not necessarily. Whether sent messages appear in the shared Sent Items folder depends on your organization’s Exchange settings. Ask the administrator to confirm the configuration if shared visibility is important for team follow-up.

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