The Conference Rooms are included with your One40 plan at no addtional charge. However Conference Calls do 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.