A method and system of erasing at least part of the location information stored on a subscriber identity module (SWI) of a mobile phone. The SIM stores the most recently used service provider in its location information. Either at power down or power up, the location information is erased so during the power up routine, the service provider search schedule will not find a service provider when it first searches the most recently used service provider stored in the location information. In this case, the service provider search routine will appropriately choose either the home service provider or a preferred service provider rather than the service provider stored in the location information. The method of erasing at least part of the location information may be carried out by a program stored on the SIM card or by a wireless network transmitting an instructive signal to the wireless device. The method and system may also provide that if the service provider stored in the location information corresponds to the home service provider or a preferred service provide, then none of the location information is erased.