Additional meeting and call-related features and issues within Microsoft Teams for business
You can refer to the AI answer, as it provides detailed information about the requirements for Audio Conferencing.
However, if you're using Microsoft Teams Free, participants cannot join meetings by dialing a telephone number. The Audio Conferencing feature, which provides dial-in phone numbers and conference IDs, is only available with eligible Microsoft Teams business subscriptions that include Audio Conferencing.
With Microsoft Teams Free, participants can still join meetings using the Teams desktop app, mobile app, or a supported web browser, but they cannot join meetings by calling a meeting phone number.
If you're using a Microsoft Teams business subscription, an administrator can enable Audio Conferencing for meeting organizers. Once configured, meeting invitations will include a dial-in phone number and conference ID that participants can use to join the meeting by telephone. Participants who dial in do not need a separate Audio Conferencing license.
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