ABSTRACTCall forwarding is a traditional telecom service that allows a user to forward incoming calls to another telephone number. This service requires the user to manually activate and deactivate the feature and therefore may not be very convenient. This paper proposes an automatic call‐forwarding algorithm (CFA) for mobile phones. By installing a software in a smartphone, call forwarding is automatically triggered (e.g., when the phone is plugged in a charger or is turned off) or disabled (e.g., when the phone is unplugged from the charger or is turned on). We investigate the performance of the CFA through analytic analysis, simulation, and measurement. Our study indicates that CFA is very feasible for commercial usage. Copyright © 2011 John Wiley & Sons, Ltd.