The invention concerns a SIM (subscriber identity module) card (1) for a subscriber on a GSM mobile radio (2) comprising a contact zone (11) to be connected with a mobile apparatus (13, 14) and electronic storage means (10) containing parameters for identifying subscribers of said mobile radio network. Said storage means can also contain one or several other identification parameters, whereby the subscribers of other systems can be identified in these other systems. The other system can accede, for example by an inductance coil (12), to said other identification parameters. The additional identification parameters can be reloaded or modified by remote control from a SIM server (3). Preferably, said parameters are transmitted by short TTP coded messages SMS, between the SIM server and the SIM cards. The invention provides the following advantage: with a single SIM card, the subscriber can be identified, for example, in a computer network, in an automatic TV payment system or in a permanent network in a financial institution or in a communication management system.