The present invention provides a method and system that enables telephone users to specify parameters that will be used in filtering incoming calls to the user's telephone device. The invention can use parameters known in telephone use such as call cost or roaming detection of mobile telephone device and user-defined settings to enable users to control costs and improve efficiency when using their cell telephones especially outside their home network and/or time zone. These call filtering parameters serve to activate the call filtering method of the present invention. The user can choose parameters that specify telephone call cost and user time zone location as threshold parameters that can trigger activation of the call filtering method of the present invention. When those parameters are exceeded, the system will enable the user-defined settings that determine how to process or direct incoming calls. The method and system of this invention can include dynamic parameters (i.e. cost) and/or static parameters (i.e. time of day) as triggering parameters. Further, the method of this invention can be automatically activated by triggers or can be manually activated by the user at any time.