You can use groups on Outlook.com to create a shared distribution list and access a group inbox with archived emails, shared files, and a group calendar. Groups allows you to connect, coordinate, and contribute to a shared purpose, all in one place.
Outlook.com service users can create and manage a group, while anyone with an email address can participate, including users with a Gmail or Yahoo email address. To create a group, sign in to your Outlook.com account and in the left-hand panel under “Groups”, select “New Group”.
We are rolling this out worldwide on Outlook.com and expect all users to have access by the end of August 2019 with expanded support to create a group in mobile in Fall of 2019.
To learn more, visit our support page.
Source: Outlook.com now supports groups