People often fail in controlling their social media use when it conflicts with other goals and obligations. To facilitate research on understanding social media self-control failures, we constructed a brief social media self-control failure (SMSCF)-scale to assess how often social media users give in to social media temptations. Social media users (N = 405) completed a survey (including a 4-week follow-up) to test the scale's psychometric properties. The self-report SMSCF-scale showed good internal consistency and test retest reliability. Demonstrating its construct validity, the SMSCF-scale was moderately related to existing problematic media use and general self-control scales. Demonstrating its predictive validity, the SMSCF-scale was positively related to social media use and feelings of guilt about one's social media use and was negatively related to psychological wellbeing. The SMSCF-scale provides a useful indicator of social media self-control failure that could facilitate future research on the psychological processes underlying social media self-control failures. (C) 2018 Elsevier Ltd. All rights reserved.