This is an Early Access feature. To enable it, please contact Okta Support.
Settings > Email & SMS
You can configure a custom email domain so that email Okta sends to your end users appears to come from an address that you specify instead of the default Okta sender firstname.lastname@example.org. This allows you to present a more branded experience to your end users. You can switch to a different custom domain or easily revert to the default Okta email domain. However, only one email domain can be in use at a time.
Okta sends your super admins a confirmation email once your custom domain is configured and operating correctly. To help ensure continuous operation, Okta polls your custom email domain once every 24 hours. If a problem occurs, Okta alerts super admins via email, and Okta-generated emails are sent from the default domain email@example.com until the problem is resolved.