In this paper, a novel method for mobile terminal (MT) subarea localisation in GSM networks is presented. No base stations position and additional hardware are required. It is a variation of the fingerprinting localisation method aiming to determine not the MT geographic position but the MT subarea and to reduce necessary initialisation measurements. Several GSM-based methods have been developed for MT localisation.The localisation method, proposed in this paper, is based on the fingerprinting method but is differentiated regarding the produced result. In this method the location server does not compare the MT collected radio network measurements with the stored radio map but with the subareas proprietary characteristics indicating the subarea where the MT is located and not the exact MT geographic position. Finally, if an LBS requires as input the subscriber subarea and not the geographic position then the novel method presented here reduces significantly the localisation initialisation requirements and computational cost in order to provide the service.