Background/Aims: Not enough is known about the psychometric properties of screening instruments for problematic alcohol consumption among adolescents. The aim of the current study was to evaluate and compare the performance of the screening instruments: Alcohol Use Disorders Identification Test (AUDIT), AUDIT-C, CRAFFT, and the alcohol domain of Alcohol, Smoking and Substance Involvement Screening Test-Youth (ASSIST-Y) among adolescents and to suggest optimal cut-offs indicating problematic use. Methods: Data was collected from a general population sample (n = 1,421) and a treatment-seeking sample (n = 59) using electronic versions of the instruments. Results: The internal consistencies for the instruments were fair (alpha’s AUDIT 0.74, AUDIT-C 0.75, CRAFFT 0.67, ASSIST-Y 0.62), and test-retest reliabilities were good to excellent (intraclass correlation coefficients AUDIT 0.86, AUDIT-C 0.93, CRAFFT 0.77, ASSIST-Y 0.63). The CRAFFT and ASSIST-Y demonstrated reasonable construct validities while factor solutions for AUDIT and AUDIT-C could not be determined. The optimal cut-off score was 2 for both CRAFFT and ASSIST-Y (61 and 73% sensitivities and 79 and 65% specificities, respectively), while sensitivity scores were poor for AUDIT and AUDIT-C. Conclusion: Based on the current sample, ASSIST-Y and the CRAFFT performed better than AUDIT and AUDIT-C. Health-care clinics working with adolescents should carefully consider their choice of screening instruments.