Hi @ben, Thank you for the details around your parent and sister company Microsoft 365 tenant setup and the SSO limitation you’re encountering in the RingCentral Admin Portal.

Because RingCentral currently allows only a single Microsoft 365 / Azure AD tenant to be connected for native SSO at the account level, adding your sister company’s tenant directly is not supported within the standard RingCentral SSO configuration.

A practical solution to this is to use CallCentral (https://callcentral.app/) as the SSO layer in front of RingCentral. CallCentral supports multi-tenant identity scenarios and can broker authentication across more than one Microsoft 365 tenant. This allows both your parent and sister company users to authenticate via their own tenant credentials while still accessing RingCentral applications.

With CallCentral.app in place, you can:
• Support multiple Microsoft 365 tenants for authentication
• Provide a unified SSO experience across parent and sister companies
• Avoid restructuring or consolidating tenants
• Maintain consistent access to RingCentral / RC applications

We recommend configuring CallCentral.app as the SSO solution and connecting each tenant there, rather than relying solely on the RingCentral Admin Portal SSO configuration.

If helpful, we can outline the setup steps and required identity provider configuration for both tenants.

Please tell me I’m not alone here.

My husband and I manage multiple RingCentral accounts for different clients/teams, and the workflow is honestly exhausting, constant logging in and out, multiple browsers open, and way too many “wait, which account am I in?” moments.

It feels way more manual than it should be in 2026.

Are people really switching accounts like this all day, or is there a better workflow/tool I’m missing?

Add-on feature

Option for Single Sign-On (SSO): Enforce SSO login only for regular user accounts, excluding non-user extensions such as Message-only, Limited, and Announcement-only extensions. These extensions do not require daily access or regular user logins.

The customer would like to use a different login name besides the email address indicated in the user details.

I have one customer who needed to have this feature because he have on company on Google and one other on Microsoft, and he can't use SSO for the both.

MRR at 100K$

Other industries do this so it is also an expectation that RingCentral should be able to

Allow 2 tenants to 1 RingCentral account through SSO.

Is it possible to have only one Microsoft 365 for SSO to be used in two different RingCentral accounts?

We would like to enforce SSO for users that are in our domain, and allow password login for users that don't have domain accounts. We do not want to enforce SSO account wide

Allow more than one source of SSO for different domains such as different Microsoft tenants. Therefore, if you have a variety of email domains amongst your users, you can specify different sources of SSO for those domain if necessary.

This would be helpful for customers who are consolidating multiple domain environments to use SSO without Federating them.