Learn about Groups in Outlook

You can create Microsoft 365 Groups from a variety of tools including Outlook, Outlook on the web, Outlook Mobile, SharePoint, Planner, Teams and more. Which tool you choose to start from depends on what kind of group you're working with. For example, at Microsoft we tend to start from Outlook when we're creating a Group organized around email and calendar. If the Group is for company-wide communication we tend to start with Yammer. For chat-based collaboration, we'd start our Group from Microsoft Teams.

• Create a group in Outlook

• Create a Microsoft Team

• Create a family group

• Create a group in Yammer

• Create a team site in SharePoint Online

• Create a plan in Microsoft Planner

When creating a group you'll need to decide if you want it to be a private group or a public group. Content in a public group can be seen by anybody in your organization, and anybody in your organization can join the group. Content in a private group must be seen by the members of the group and people who want to join a private group have to be approved by a group owner.

Neither public groups nor private groups can be seen or accessed by people outside of your organization unless those people have been specifically invited as guests.

For more information on changing your groups from Public to Private (or vice-versa), see Make Microsoft 365 groups public or private.

Owners, Members and Guests

Group owners are the moderators of the group. They can add or remove members and have unique permissions like the ability to delete conversations from the shared inbox or change different settings about the group. Group owners can rename the group, update the description or picture, and more. If you're familiar with SharePoint roles, then a group owner is a site collection admin.

Group members are the regular users in your organization who use the group to collaborate. They can access everything in the group but can't change group settings. In the SharePoint world they are site members. For information about adding or removing group members, see Add and remove group members in Outlook.

Guests are like group members, but they are outside your organization. By default, your users can invite guests to join your group, and you can control that setting. For more information, see Guest access in Microsoft 365 groups.

Select the type of Groups you want to use:

• Outlook

• Microsoft Teams

• Yammer

If you prefer the shared inbox mode of collaboration, then the groups experience in Outlook is for you. By creating a group in Outlook, you’ll get:

• Shared Inbox– For email conversations between your members. This inbox has an email address and can be set to accept messages from people outside the group and even outside your organization, much like a traditional distribution list

• Shared Calendar – For scheduling events related to the group

• SharePoint Document Library– A central place for the group to store and share files

• Shared OneNote Notebook – For gathering ideas, research, and information

• SharePoint Team Site– A central repository for information, links and content relating to your group

• Planner– For assigning and managing project tasks among your group members

You don’t have to manually create any of those resources; creating the group automatically creates them for you and assigns the necessary permissions for your group members so they can start using them right away.

You can access these resources through Microsoft Outlook for Windows, Outlook on the web, Outlook for Mac (shared inbox only), or Outlook mobile. 

With the Microsoft 365 Groups hover card, you have quick access to shared group resources. Just hover over a group name in Outlook on the web or SharePoint.

• Get started with Microsoft 365 Groups in Outlook

• Video: What can you do with Microsoft 365 Groups in Outlook? (YouTube)

• Join a group in Outlook

• Guest access in Microsoft 365 Groups

• Get more with Microsoft 365 Groups in Outlook

An excellent way to keep in touch with your group is Microsoft Teams. Microsoft Teams is the inner loop for your team – a persistent, chat-based workspace where you can have informal, real-time, conversations around very focused topics or specific sub-groups within the group. Although the Teams integration doesn't come automatically, you can easily create a Teams group based on your Microsoft 365 Group.

• How do I get access to Microsoft Teams

• Microsoft Teams Quick Start

• Teams Help Center

• Welcome to Microsoft Teams

After a Group outlives its intended purpose, you can delete it to free up system resources and to remove the group from being listed or displayed. See: Edit or delete a group. If you don't want to have to remember to delete outdated groups your administrator can set expiration policies that will cause old groups to expire and be removed automatically after a specified period of time. See: Microsoft 365 Group Expiration Policy.

There are three primary models of provisioning Microsoft 365 Groups: Open, IT-led, or Controlled. Each has its own advantages.

Model	Advantages
Open (default)	Users can create their own groups as needed without needing to wait for, or bother, IT
IT-led	Users request a group from IT. IT can guide them in selecting the best collaboration tools for their needs
Controlled	Group creation restricted to specific people, teams, or services (See: Control who can create Microsoft 365 Groups)

If you want to control how your Microsoft 365 Groups are named, you can use naming policy to force Group names to adhere to certain standards, including prefixed or suffixes, as well as blocking objectionable names. See Microsoft 365 Groups Naming Policy for more information.

Every group has at least one owner that can add or remove members and do some basic curation of the group and its content. Usually the owner does that in Outlook. See: Add and remove group members in Outlook. If a group's owner (or owners) leaves the organization for any reason, the administrator can assign a new owner to the group. See Assign a new owner to an orphaned group.

Additionally, if you have Exchange Online Administrator permissions you can administer your groups from the Microsoft 365 Admin Center (See Manage Group membership in the Microsoft 365 admin center) or from PowerShell (See Manage Microsoft 365 Groups with PowerShell.

There may come a time when you want to delete a group from your tenant. For information on how to delete a group see: Delete a group. If a group is accidentally deleted, admins can restore that group for up to 30 days. See: Restore a deleted Microsoft 365 Group.

If you prefer a more automated way to manage the lifecycle of your Microsoft 365 Groups, you can use expiration policies to expire groups at a specific time interval. The group's owners will get an email 30, 15, and 1 day before the group expiration that allows them to easily renew the group if it's still needed. See: Microsoft 365 Group Expiration Policy.

• Allow members to send as or send on behalf of a Microsoft 365 Group

• Migrate distribution lists to Microsoft 365 Groups

• Guest access in Microsoft 365 Groups

• Manage your group-connected team site settings

Group Limits

Maximum...	Value
Owners per group	100
Groups a user can create	250
Groups an admin can create	Up to default tenant limit of 500K
Number of members	More than 1,000, though only 1,000 can access the Group conversations concurrently. Users might notice delays when accessing the calendar and conversations in very large groups in Outlook
Number of Groups a user can be a member of	1,000
File storage	1 Terabyte + 10 GB per subscribed user + any additional storage purchased. You can purchase an unlimited amount of additional storage.
Group Mailbox size	50 GB

The default maximum number of groups that an Microsoft 365 organization can have is currently 500,000.

If you are planning to use the feature "Group Writeback" from Azure Active Directory Connect tool, the maximum length is 448 characters related to the "Description" attribute.

For more information on SharePoint Online storage see SharePoint Online Limits and SharePoint Online software boundaries and limits.

Managing your Microsoft 365 Groups is more effective when you have actionable information about Groups usage. The Microsoft 365 Admin Center has a reporting tool that can let you see information such as storage use, how many active Groups you have, and even how your users are using the Groups. See: Microsoft 365 Reports in the admin center for more information.

Microsoft 365 Groups gives you a number of tools for compliance, information protection, and eDiscovery.

• Overview of retention policies

• Overview of labels

• Create or remove an in-place legal hold

• Create a preservation policy

• Content Search in Microsoft 365

• Introduction to IRM for email messages