Beware! New charges are now sometimes being levied on participants of Audio and Web conferences. If your conference invitation gives you the option to listen to the audio portion through your computer speakers, you might be charged if you use your telephone to dial in to listen.
When the third party is setting up the conference, it is a less expensive option if they select to broadcast the audio through the computer. Some conferencing services still provide a back-up phone number to dial. Since the party originating the conference did not elect to set up the conference with a toll-free number, the service might pass along the fees to your network carrier. In these instances, the fees might then appear on your monthly invoice from your network provider.
To be on the safe side and to know what your exposure might be, contact your network provider to find out what their policy is regarding audio and web conferencing charges.