Microsoft 365 (Outlook on the web | Outlook for Windows/Mac) - Send as or Send on-behalf of another account

There are times when you need to send a message either as a another account or on-behalf of another account. Before you proceed, make sure you understand what send as permissions or send on behalf permissions are.

This document assumes you have been granted send as or send on behalf permissions to another account. If these have not been granted yet, please refer to the Microsoft 365 - Manage Full Mailbox, Send As, and Send on Behalf of Permissions document.

Note: If you are linked to a service account, you are automatically provided "full mailbox" and "send as" permissions to the account. This means you can open up the mailbox and 'send as' that account.

Important: In order to send-as or send-on-behalf of an account via Outlook desktop client, the account must be visible in the Global Address List (GAL). You can verify the visibility of the account using these instructions: Microsoft 365 - Show or Hide Service Account within Global Address List. If the account is hidden, you must make it visible. Office 365 service accounts are hidden by default within GAL.

Outlook on the web

      1. Log into Office 365 via Outlook on the web. Make sure you select the account that has been assigned Send As or Send on-behalf of.
      2. Click the new mail button, new mail button, above the folder list. A new message form will appear in the reading pane.
      3. Click on the "Options" menu and place a check mark within "Show From" box.
      4. Click on "From" field and select "Other Email Address..."
      5. Either select the desired address from the drop down list or enter the address you have permissions to 'send as' or 'send on behalf' of.
      6. Enter the desired values within all the other fields and send the email.

Outlook for Windows

    • Important: In order to send-as or send on behalf of an account via Outlook desktop client, the account must be visible in the Global Address List (GAL). You can verify the visibility of the account using these instructions: Microsoft 365 - Show or Hide Service Account within Global Address List. If the account is hidden, you must make it visible. Office 365 service accounts are hidden by default within GAL.

      1. On the Home tab, select New Email.

        Click New Email

      2. Click the from box and select Other E-mail Address... from the dropdown.

        • Note: The From field is hidden by default. If the From field is hidden, select Options from within the message you are composing, then select From.

          Click Options, then From

      3. Within the Send From Other E-Mail Addresses window, click From.

        Click From

      4. Make sure More columns and Global Address List are selected.

        Select More Columns and Global Address List

      5. Type the email address of the person you want to send as or send on behalf of and click Go.

        Type email address

        Then, select the name of the person you want to send as or send on behalf of, and click OK.

      6. Back on the Send From Other E-mail Address window, click OK.

        Click OK

      7. Compose a message as usual and send when ready. Depending on access, the recipient will see one of the following:

        • Send as permissions: Your message will appear to have come from the user that granted you this permission.
        • Send on behalf of permissions: The "From" address in any message sent by you will indicate that the message was sent by you on behalf of the user that granted you this permission.

      If you do not have permission to send from this account, you will receive an email saying Your message did not reach some or all of the intended recipients, followed by the subject, date and time the message was sent and a list of recipients. If you believe you should have permissions to someone's mailbox, you should contact them for verification or ask them to grant you permissions.

Outlook for Mac

    • Important: You must first be subscribed to the account before you can send a message from the account. In addition, to send-as or send-on-behalf of an account via Outlook for Mac desktop client, the account must be visible in the Global Address List (GAL). You can verify the visibility of the account using these instructions: Microsoft 365 - Show or Hide Service Account within Global Address List. If the account is hidden, you must make it visible. Office 365 service accounts are hidden by default within the GAL.

      1. Start Outlook.

      2. Create a new message or reply to an existing message.

      3. From within the "From:" select box, select the account you want to send from.

        Note: If the account does not show up in the list, you must first subscribe to the account.

      4. After you compose the message, send it.

        If you have "send as" permissions, the recipient(s) will see the message from the account you are sending as.

        If you have "send on behalf of" permissions, the recipient(s) will see the message from "your_account on behalf of from_account".

      Note: We recommend you send a test message to yourself to make sure you have the appropriate permissions. If you don't, the message will stay in your "Drafts" folder. If this occurs, verify that you have the appropriate permissions to the account you are attempting to send from.

See Also:



Keywords:microsoft office365 o365 m365 microsoft 365 send as permissions granted delegate delegated grantee outlook on the web owa 2019 2016 proplus windows mac os macintosh office on behalf of service account linked netid sending emails delegates read write subscribe owner none contributor reviewer non-editing author publishing editor editor publishing author author custom availability only limited details full details editor delegate   Doc ID:40879
Owner:O365 S.Group:Microsoft 365
Created:2014-06-07 22:37 CDTUpdated:2023-03-10 14:00 CDT
Sites:DoIT Help Desk, Microsoft 365, Wisc Account Admin
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