Audio conferencing solutions are the oldest among the main three. These can include three phone lines bridged together to create complex outsourced services. It can also mean the lower cost solution of a two-party call, where a speaker phone is utilized in order to let everyone around a table participate in the call with the party on the other end.

This is the type of conference call in which the most people have participated. They can be very effective despite their limitations. This limitation is the same as with any other telephone. For one thing, it means that you can only hear what the person is trying to say, but not actually see it. Also, if anyone is too far from the microphone, or the phone isn't of very good quality, or even if a person doesn't speak up enough, then it makes communication difficult. Furthermore, if the phone call is long distance, then at least one of the parties will need to pay the long distance bill - unless an 800, 877, 888, or other toll free number is available