IntroductionSocial media use has grown dramatically since its inception in the early 2000s and has further increased during the COVID-19 pandemic. Problematic use of social media (PUSM) is a type of behavioural addiction which has generated increasing interest among mental health clinicians and scholars in the last decade. PUSM is associated with multiple psychiatric conditions and is known to interfere with patients’ daily functioning. There is no single accepted definition of PUSM, nor means of measuring it, in the literature. The Bergen Social Media Addiction Scale (BSMAS) is a helpful tool for identifying PUSM. This paper aims to validate BSMAS and to translate it from English into French, with the goal of making this clinical screening tool for PUSM available in French-language contexts.MethodThis study explored the psychometric validity of the French version of the BSMAS in a sample of 247 adolescents, who were either psychiatric inpatients (the hospitalized group, n = 123) or recruited in local high schools (the community group, n = 124).ResultsThe adolescents in the sample reported an increase in their social media use during the COVID-19 pandemic. This increase was more pronounced in the hospitalized group. Confirmatory factorial analysis showed an excellent fit, very good internal consistency and established convergent validity for the French version of the BSMAS. A total of 15.4% of the hospitalization group and 6.5% of the community group met the recommended clinical cutoff of 24 on the BSMAS, suggesting problematic use of social media.ConclusionsThe French version of BSMAS is a psychometrically validated and clinically useful tool to screen for PUSM in adolescents.