This is because there is truly no such thing as a “free” conference call. The companies who offer services like this make money by charging a high connection fee for other carriers to route calls to them. They then offer the conferencing service for free to users. The carriers who deliver calls to them are footing the bill for their service.
Here is how it works: normally, carriers charge a small fee to connect a call. So, if you are in Phoenix using Centurylink phone service and you call someone in Los Angeles using Verizon phone service, Verizon will charge Centurylink a small charge, typically a fraction of a penny, to make the connection. When calls are routed in the other direction, i.e. from Los Angeles to Phoenix, the connection fee is assessed in the other direction, and typically these charges in both directions cancel each other out. These connection fees are determined locally, and it is possible for a particular calling area to establish an extremely high connection fee.
So, “free” conference calling services have set up shop in sparsely populated states, such as North Dakota, and they establish a high connection charge, in some cases dollars per call. Since the amount of incoming traffic related to these conferencing services is much greater than the outgoing traffic from such a sparsely populated area, the result is an influx of revenue.
Because of this practice, many carriers block calls to these area codes by default, or they charge for calls to these area codes. For example, Google Voice charges $0.01 per minute to call these area codes. Phoneware blocks calls to these areas by default.
As an alternative to free conference calling services, Phoneware offers a flat rate audio conferencing service for $2.00 per month that includes up to 100 participants, call recording, host controls, web access, and much more. Plus, when your conference call attendees join the conference call, they are NOT presented with a “Thank you for calling FREE CONFERENCE CALLING”, which does not sound professional.