Hi ​@Callen, welcome to the Box Community!

Primary admins can update the email addresses of managed users by Configuring and Editing Users. To do this, navigate to the Admin Console > Users and Groups, then click on the Managed Users tab.

This process only updates the user’s email address; the user's password will remain unchanged.

If SSO is enabled, please refer to this article: Changing an Email Address for a Single Sign-On Account

Feel free to reach out if you have any other concerns or questions.