Conference Calls use your “Available Lines”.

Each participant uses one of your available lines. The max participants you can have on a conference call is based on how many available lines you have.

i.e. If 10 participants call into a conference room, and the Conference call lasts 30 minutes, you will have 10 lines busy for those 30 minutes. At the same time if you only had 5 lines then only 5 of the 10 participants could call into the conference room.

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