On-premise user unable to chat with TeamsOnly user.

Copper Contributor

Our organization purchased only 100 o365 licenses, which is less than 500. So all online users automatically become TeamsOnly. I can't change TeamsOnly mode due to this microsoft policy https://support.microsoft.com/en-us/help/4465277/microsoft-teams-now-the-primary-client-for-meetings....

Now, thanks to federation, on-premise SFB users may communicate with other tenants' Teams users. However, can't communicate with people who are in the same organization but online. And that is kinda stupid. 

I hope that people will notice that o365 is much more convenient and purchase more o365 seats. One of the most amazing cloud features is Teams, it gives excellent collaboration experience. However, if online users can’t communicate with on-premise users, they won’t use Teams at all. Is there any possibility to let Teams users communicate with on-premise SFB users?

12 Replies

Hi @Аллдар Бухаев,


to allow your online and on-prem users to communicate with each other you have to configure SfB Hybrid.

This can be considered as a federation between online and your on-prem environment.

More details can be found here:






@Paul Lange 

Thanks for response, I already configured the hybrid setup. And moved users online.

Now in my hybrid environment, there are online users and on-premise users, who can't communicate with each other. Online users are TeamsOnly (I described above), they may communicate only with online users. On-premise users may communicate only with on-premise users.

you need to contact support to get your tenant switched over to still allow the other modes so you can transition since you are not a new tenant and coming on as hybrid you should still be able to configure the other modes.

However. Once you introduce. Teams and hybrid I’m pretty sure that all your Onprem users require a Skype online license so that the gateway that handles the interop back to onprem will function properly.
Thank you Chris - True you have to have the SfB* modes for you on-prem users - I quick checked the interop part with an on-prem user without having an O365 license and it worked instantly. But there is maybe more for a full picture off this.
Cool. Thanks for verifying that. That’s same domain teams user to a same domain onprem Skype user?
Yes. Same domain for both users.

Thank you guys,

@Paul Lange,

Microsoft support answered that to enable interop modes I need a tenant more than 500 seats. 

How to let onpremise users communicate with online TeamsOnly users? I don't want to purchase online licenses for on-premise users. 

From my understanding, you don't need a license for the on-prem users.
You should explain to the support that you have a hybrid environment with users hosted on-prem. For those users, you need to configure one of the SfB* coexistence modes. Teamsonly as a coexistence mode is not working for them.

@Paul Lange 

I explained to support everything, and they replied:

"Teams only user cannot communicate with SFB on-prem user"

"New customers that have fewer than 500 seats can only use Teams only mode"


So now I am looking for a workaround.


Let me see if I can get in touch with someone that might be able to help. Can’t make promise but will reach out.

@Аллдар Бухаев 

I know this is old thread, but did you get any solution of this issue?

HI team,
we are also facing the same issue on skype for business hybrid setup
> we are able to migrate users from onpermise to office365 skype for business.
>onpremise users are able to communicate with onpremise and teams to teams
> onpremise users not able to communicate with teams and vice versa.
can anyone please help.