Abstract: A method is provided for a mobile station to calculate the time intervals at which it monitors cells in a cellular phone system to find the mobile station's home network in the phone system. The monitoring varies with the rate at which the mobile station reselects proximate cells to locate itself in a telephone network. The time between cell selections is used as an indication of the mobile station's mobility. The variable search intervals, determined by the time intervals at which the mobile station reselects cells, is limited to insure that the mobile station at least monitors for its home network at a minimum specified interval of time. An apparatus is also provided to initiate home network monitoring at time intervals related to rate at which cells in a cellular phone system are reselected by a mobile station.