Mobile phones appear to have become one of the main entertainment features in adolescents’ life, which has also been suggested to be potentially addictive. A shortened version of a scale used to detect this potential addiction, the Mobile Phone Problematic Use Scale (MPPUS-10; Foerster, Roser, Schoeni, & Röösli, 2015) has been extracted from the Mobile Phone Problematic Use Scale for Adolescents (MPPUSA; Lopez-Fernandez, Honrubia-Serrano, & Freixa-Blanxart, 2012). To validate this shortened scale, a cross-national study surveyed 1391 high school students in both Spain and Greece, assessing both socio-demographic variables and self- perceived mobile use dependency. The MPPUS-10 exhibited good factorial validity, good reliability, and similar mid scores in both countries. Results from sub-scale symptomatology showed consistency in elevated levels of craving, withdrawal, and loss of control related to mobile phone use in both countries. This study presents evidence of self-perceived mobile phone dependence in south-European high school students, but more research is needed.