As there are a variety of options when creating an e-mail address in Office 365’s Exchange Online, it’s important that you look at the different choices and make sure you pick the best fit for your particular scenario.
Primary Address – this is the primary e-mail address for a user with a paid Exchange Online subscription. All e-mail sent by the user from their Exchange Online mailbox will appear as being from this address by default. It is usually also the User ID for connecting to Exchange Online and Office 365.
Alias – each user with an Exchange Online subscription can have multiple e-mail aliases in addition to their primary e-mail address. For example, Jane Smith’s primary e-mail address might be firstname.lastname@example.org, but she could have an e-mail alias of email@example.com. Any e-mail sent to the alias goes into the same mailbox as the primary address.
Distribution Group – a distribution group can be set up to send multiple users a message at the same time. If you frequently need to send e-mails to the entire marketing team, for example, you might want to send to firstname.lastname@example.org rather than putting in everyone’s individual e-mails each time. The message goes into each user’s primary mailbox, but rules can be added to the mailbox to move these messages to a particular folder if needed. Users can also be given permission to send messages out from this group address. You can set up a distribution group in the Exchange Online admin center.
Shared Mailbox – if you need a completely separate mailbox for a general e-mail address, such as email@example.com, you can utilize a shared mailbox. This is a complete mailbox with e-mail, calendar, contact, and task capabilities. A user with an Exchange Online subscription can access it from their Outlook client or the Outlook Web App in addition to their own mailbox. As permissions are granted to users for the mailbox, it does not come with its own password and thus cannot be connected to mobile devices.
E-mail aliases, distribution groups, and shared mailboxes can be set up by an administrator through the browser-based Exchange Online portal. Whether you choose to add an e-mail alias or create a distribution group or shared mailbox, Microsoft does not charge you beyond the per user subscription fee you’re already paying, so it’s definitely something to consider taking advantage of.