Ability to connect existing SharePoint team sites to Office 365 Groups is coming later this year


Important sets of announcements today from the SharePoint team, including this specific one coming later this year:

  • The ability to connect existing SharePoint team sites to Office 365 Groups, so you can augment existing sites with shared conversations, calendar and Planner.

74 Replies
I assume this is really connecting existing "SITE COLLECTIONS" to groups, and not sub-sites? collections.  That would be no good.  Our site collections are per regional office and our subsites are departments.  We NEED to be able to connect an 0365 group to a sub-site.  Please clarify Microsoft.

best response confirmed by VI_Migration (Silver Contributor)

Hi all - yes our plan is to provide the ability to connect only root site collections to new Office 365 Groups.  We've considered enabling subsite-to-group connections, but there are enough gotchas both architecturally as well as from a design standpoint in delivering an experience that is comprehensible to most humans.  One example is that when we start rolling out classification-based policy (e.g. Confidential classification equates to group guests being disabled, SharePoint external sharing turned off, etc. - this is just an example for discussion), those policies apply at the site collection container level.  If we enabled subsite connection to groups, we would have to deal with site parent-child policy conflicts, inheritance-based permissions, etc.  Not saying it's impossible but cleary stands in the way of shipping an experience sooner. 


Having looked at all site collections in the service, the vast majority are flat (i.e. no subwebs), for which this experience should work seamlessly.  That said, we acknowledge that there are some very active site collections with subsite hierarchies.  For these subwebs, there are a couple of paths to get to 'modern'.  One is a migration effort from subsite to root site collection, and then connecting the collection to a new group with the feature described in this thread.  The other, is a 'modernize this site' type of experience that brings the classic subsite to the modern experiences without a group connection.  This is also a body of work we are investing in and will share additional details in the future.


Hope this helps to clarify.  We'll definitely be talking more about this in the coming months as we make progress on the feature.





 @Christine Stack we've started doing what @Tejas Mehta mentioned and bought a migration tool to just move existing content into newly created Group sites (root site collections).  


im super suprised to hear the stats on the subsites, weve done quite a lot and even more since the expansion of site collection sizes. we typically had one SC for projects, one for workgroups, one for each operating company, etc.  in any case it is painfully clear information architecture is dead, might as well embrace it :grinning_face:


for us the migrations arent too painful, though we dont have a lot of complexity in the sites we are migrating (eg no workflows etc)

This is dissapointing. This still means there is a large migration process in the future for us if we ever want to start using groups or teams in our org. 

 Tejas Mehta,


I really apreciate the quick answer.  Not exactly what I was hoping since we have many subsites but at least we know where we are moving to.  I am that we will leave the current structure "as is" create new 0365 modern sites and just put a hyperlink to the old subsites sites.  


It is very easy to convert a DL to an 0365 group but all our permissioning and mailing lists are mail-enabled security groups.  Is it easy to convert those to 0365 groups?



Are there any plans to connect pre-team site SharePoint Online sites to O365 Groups?

Christine there is no automatic upgrade mechanism to convert security groups to Office 365 Groups.

Nick, curious to hear more about your scenario?  Our plans are to enable group connection for classic team site templates only.

Can you convert security groups to 0365 groups with powershell?

Christine, is this a question for me regarding the group connection to existing site collections?  If so, yes we are planning to provide PowerShell cmdlet to achieve the site-to-group connection.

We are SharePoint Online ONLY. Each regional office has a site collection with departments and projects as subsites. It is the subsites that we need connected to 0365 groups and that cannot be done. There is also a Committees site collection that has people from each regional office and all sites have a global nav.

We create site collections per customers and sub sites per projects. Real collaboration occurs on project so I was expecting a Group at the project level.


As we have a lot of sites (150k customers / 180k projects) we didn't want to create all the sites as site collection.


I was really hoping for sub sites Groups.

Tejas, We would need subsite to 0365 group connection and my understanding is that will not be happening just Site Collection to group connection.

Sitecollection 'Projects' and underlying project sites (or 'Teams' and team sites) is a common use case in tons of SharePoint real world implementations. So we would easily accept any further restrictions if we could tie sub-sites to teams or groups.

If not, the implementation will not really help.

@Christophe Fiessinger - I'm surprised more tenancies aren't making use of sub-sites. We followed our same onPrem architecture of creating a few top level site collections and then creating multiple site collections under them. The ability to connect a Group to a Sub-Site is going to be critical to our business given the subsites in the structure of PPPM ( Portfolio, Programme, Project management) processes we follow.
Is this something Microsoft are considering, on their roadmap?


We also did it this way to work within the 2,000 subsite per site collection limit, while also maximising our protection from the 500,000 limit of site collections per tenancy.


Any advice / guidance - greatly appreciated


Hi Graham, thanks for your feedback.  At present we don't have plans to enable connection of subsites to Office 365 Groups.  There are numerous hurdles and technical complexities we'd need to overcome, e.g. how do you treat group privacy or external guest access to parent (or child) sites that have been connected to groups themselves or how would users of other group workloads (e.g. mailbox) expect to interact with parent/child resources outside of SharePoint?  Implementing the corresponding constraints and representing them in a way that site owners can interpret meaningfully in our interface is a challenging task.



Out of curiosity - are you anywhere near 500k site collections in your tenant, or foresee breaking through that number?