In the on-premises Exchange Server, there are three basic group types: distribution groups (a.k.a. distribution lists), dynamic distribution lists, and security groups. Office 365 presents another type: Office 365 Group. After a quick look, you can see that those Office 365 Groups can be used for the same purpose as distribution lists. The thing is, on numerous occasions, you can see that distribution lists are becoming obsolete, while Office 365 Groups are a recommended and a continually improved feature. So how are distribution groups different from Office 365 groups? I explain shortly in the article below.
The quickest way to explain the difference between Office 365 groups and distribution lists is to say that Office 365 groups are distribution lists plus more. For a simple comparison, take a look at the table below. If you want a more in-depth comparison, see the sections below the table.
A quick comparison between Office 365 Groups and Distribution lists
The table below shows a brief comparison between Office 365 Groups and Distribution Lists:
Office 365 Groups vs distribution lists
|Distribution list||Office 365 Group|
|Functionalities||Enables users to send emails to all members of a group.||In addition to the distribution list’s feature, integrates with SharePoint, Yammer, Team, Planner, OneNote, and PowerBI.|
|PowerShell management||Yes, sample cmdlet: Set-DistributionGroup.||Yes, sample cmdlet: Set-UnifiedGroup.|
|Can send emails to all members of a list||Yes, both for internal and external senders.||Yes, both for internal and external senders.|
|Shared inbox||No, emails are only distributed to members.||Yes.|
|Defining access type||Not available.||The option is available.|
|Document library||Not available.||Set up automatically in SharePoint.|
|Shared calendar||Not available.||Set up automatically.|
|Required license||Any AAD subscription (including free.)||Free AAD subscription is enough for most Office 365 Groups' features. For a full list of available features visit this article.|
|Restore a deleted group||Not available.||Office 365 group can be restored for up to 30 days after deletion.|
|Dynamic membership||Possible with Dynamic Distribution Groups.||Requires Azure AD premium subscription.|
As I mentioned before, Office 365 groups are distribution lists “plus more”. Before I specify what does “plus more” incorporate, I will quickly describe the similarities between the two groups.
Office 365 groups and distribution lists – similarities
Distribution lists are known to both Office 365 admins and even the oldest Exchange on-premises experts – there are even some stories with Distribution lists as the main character, like Bedlam DL3. DLs have been around for a while, and the idea behind them is quite simple. They allow users to write or forward their messages to a group of users, whether it is a single department, members of the same office, or the whole company. For those who work most of their day in Outlook, it is a feature used so much that they do not think about it.
Another similarity is that both distribution lists and Office 365 Groups are managed the same way. Although the cmdlets used to work on them are a bit different, their attributes are quite similar and in most cases. In fact, if you changed the New-DistributionGroup cmdlet to New-UnifiedGroup while leaving the same parameters, the code will most likely be executed with no issues.
Office 365 groups and distribution lists also look very alike from the EAC point of view – they both use the same wizard to create them. But that is as far as the similarities go.
Differences between Office 365 groups and distribution lists
The most important reason to use Office 365 groups is enhancing collaboration. While distribution lists have the same purpose, Office 365 Groups go a few steps further.
The first difference is that Office 365 groups have a shared mailbox and calendar. This means that emails are not only distributed to all members of the list – they are stored in a separate mailbox. The shared calendar gives the functionality previously reserved for public folders.
But the differences mentioned above fall into the category of Outlook and OWA features. Office 365 can do more than that. Depending on what functionalities you need, a group can be created along with an associated SharePoint library, OneNote notebook, Microsoft Teams, Yammer, Planner, and PowerBI.
You can see another set of differences in EAC. Despite the similarities to a distribution list, an Office 365 Group has two additional fields: Privacy and Subscribe members.
Additional options available for Office 365 groups
Privacy, (or –AccessType in PowerShell) defines the type of a group. Anyone can see the content and conversations of a Public group. What is more, anyone can join such a group, without approval from a group owner. Private groups are different: only members can see the content of those groups and joining such a group requires approval from a group owner. This is a clear improvement over distribution lists, as the only way to limit access to groups was to change role assignment policy not to include MyDistributionGroups and MyDistributionGroupMembership roles.
Subscribe members – Subscribing a group is not the same as joining the group. If you subscribe to an Office 365 Group, it is like saying “I want to know everything that happens there.” The Subscribe members option makes subscriptions of new members automatic. This option is risky, as it greatly increases the number of notifications users will receive, especially if Office 365 Groups are used a lot. While this is a good way to be up to date, too many notifications can greatly reduce performance – as they tend to distract users. Fortunately, users can change their subscription settings, which overrides the automatic subscription option.
As you can see, Office 365 Groups and distribution lists are very similar only at first sight. Although both kinds of groups can be used for the same purpose – sending emails to many recipients – Office 365 groups offer much more possibilities which can improve collaboration in an Office 365 organization.