Phone System Provides PBX Functionality for Teams

• Phone System is Microsoft’s hosted equivalent to an on-premises PBX system, providing management and routing for voice calls in Teams.
• Phone System could enable Teams to replace or integrate with a customer’s existing on-premises PBX or call center software.
• While Phone System manages and routes calls, the Calling Plan or Direct Routing service (or both) are required to provide a “dialtone.”
• The service is included only in Office 365 and Microsoft 365 E5 plans and must be purchased as a per-user add-on to any other plan.

Phone System (formerly called Cloud PBX) is a service offered by Microsoft that provides the hosted equivalent of an on-premises private branch exchange (PBX) system for users within the Teams collaboration platform and the Skype for Business Online service that Teams will eventually replace. Phone System will be a required purchase for any customer that wants to allow their Teams users to place or receive calls over the public switched telephone network (PSTN). In conjunction with Calling Plan or Direct Routing, Phone System could allow a customer to replace or augment their on-premises phone systems, provide telephony service for branch offices, or integrate Teams with existing PBX or call center installations.