Information processing system capable of calculating communication fees corresponding to communication utilization forms

A method by an information processing apparatus for calculating a communication fee in a particular utilization form among a plurality of utilization forms of an information terminal and an information disclosure apparatus connected to said information processing apparatus through a network, said method comprising:

• said information processing apparatus storing calculation equations for calculating said communication fee corresponding to an identifier of said information terminal regarding first and second subscription courses whose said particular utilization forms are different each other, and first subscription information including information on a date and time of starting said first subscription course, in a first storage device;
• said information disclosure apparatus storing second subscription information including information that said second subscription course will be selected instead of said first subscription course corresponding to an identifier of said information terminal and a date and time of starting said second subscription course in a second storage device;
• said information disclosure apparatus transmitting said second subscription information to said information processing apparatus upon receipt of a notification that disclosure of said second subscription information is permitted from said information terminal through said network;
• said information processing apparatus, upon receipt of said second subscription information from said information disclosure apparatus, storing said second subscription information in said first storage device;
• said information processing apparatus recording a communication amount by a communication in said particular utilization form performed by said information terminal and a communication date which indicates a date and time at which said communication has been performed in said first storage device;
• and
• said information processing apparatus determining whether or not said communication date and time is before said date and time of starting said second subscription course, calculating said communication fee by using said communication amount and a calculation equation for said first subscription course when said communication date and time is before said date and time of starting said second subscription course, or calculating said communication fee by using said communication amount and a calculation equation for said second subscription course when said communication date and time is at or after said date and time of starting said second subscription course.