Office 365 (Outlook on the web | Outlook 2016) - 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 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). If the account is hidden, you must make it visible. Office 365 service accounts are hidden by default within GAL.

Outlook on the Web

Outlook 2016 for Windows

Outlook 2016 for Mac