The KADS-6 is a self-report assessment instrument known for its ease application in assessing depression in young people. This study aimed to contribute to the validation of the Portuguese version of this tool and analyze its psychometric characteristics in comparison with other self-report instruments for depression in adolescents, in Portugal. Two samples were collected, a non-clinical group of in school youth (n=773; 52.4% male) and a clinical sample (n=134 youth; 44% male). Comparisons also used the Beck Depression Inventory (BDI-II) and the Children's Depression Inventory (CDI). Results: The factor analysis revealed the unidimensionality of the measure. The KADS-6 demonstrated good internal consistency (Cronbach's alpha) in both clinical (.74) and school (.80) samples. Its convergent validity with the BDI-II and CDI was r=.44; r=.61, respectively in the clinical sample and r=.60; r=.57 in the school sample. The KADS-6, a short and time efficient instrument, showed good psychometric characteristics in terms of internal consistency and convergent validity in comparison with the BDI-II and the CDI. Given its ease of use and scoring, the KADS-6 could be considered for use in both school and clinical settings when addressing adolescent depression.