Abstract: A method and structure for increasing the security of a cordless telephone system by automatically altering the security code information stored in the cordless telephone handset and base unit. Thus, without requiring effort on the part of the user, the security codes are updated to differ from the previous security code setting, while always maintaining corresponding security codes in the handset and base unit. In one embodiment, the updating of the security code is performed at any convenient time interval or in response to any convenient activity, such as the placement of the handset into the base unit for storage and recharging. In one embodiment when the security code is to be updated a new security code is generated in a predetermined manner, for example by random number generation, by the handset.