NOTE: You must have admin permissions in order to do this.

1. In the admin center, go to the Users > Active users page.
2. On the Active Users page, select the user > click on … next to Export users > click Manage username and email. You won’t see this option if the person doesn’t have a license assigned to them.
3. You should see the below pop-up from the right-hand side of the screen:
   
   In the Username field, type in the front half of the alias. Where it says Domains, select a domain from the drop-down menu. When you’re done, click Add.
4. Once you have added all the aliases for this user, click Save changes to confirm and finish.
5. Wait 24 hours for the new aliases to populate throughout Microsoft 365.
   The user will now have a primary address and an alias.
   For example, all mail sent to Eliza Hoffman’s primary address, Eliza@NodPublishers.com, and her alias, Sales@NodPublishers.com, will go to Eliza’s Inbox.
6. When the user replies, the From address will depend on their Outlook client. Outlook on the web will use the alias at which the email was received.
   Outlook desktop will use her primary email alias.
   For example, let’s say a message is sent to Sales@NodPublishers.com, and it arrives in Eliza’s inbox. When Eliza replies to the message using Outlook desktop, her primary email address will appear as Eliza@NodPublishers.com, not Sales@NodPublishers.com.