Microsoft 365 Business Voice
can only be added to existing Office 365 or Microsoft 365 subscriptions
that include Microsoft Teams
; qualifying plans include Office 365 Business Essentials, Business Premium, E1, E3, A3, or A3; Microsoft 365 Business, E3, or A3 for up to 300 users. You cannot purchase Microsoft Business Voice without an existing Office 365
or Microsoft 365 subscription.Microsoft 365 Business Voice includes the phone system, audio conferencing and domestic calling with international calling available as an add on.