Many schools and communities conduct regular surveillance surveys to monitor student mental health risk. These surveys rarely ask about use of mental health services, despite the potential importance of this information to support service planning and resource allocation. The current study developed and tested the Adolescent Mental Health Support Scale (AMHSS), a brief self-report measure that can be added to student surveillance surveys to evaluate adolescent mental health service use. The AMHSS includes questions assessing desire to use mental health services, use of mental health services, and barriers to accessing school mental health services. The development process included: (1) a search of the literature for existing questions to include in a question bank for use or adaptation for the new measure; (2) focus groups with adolescents to learn about their conceptualization of mental health services and obtain feedback on candidate survey items; (3) expert review and validation by school-based mental health service providers and research experts; and (4) survey administration and evaluation of psychometric properties. The AMHSS was administered as part of the fall 2018 MetroWest Adolescent Health Survey to students in 27 communities in the MetroWest region of Boston, Massachusetts. Analysis of survey results from 12,924 middle and 26,318 high school students indicated that response patterns were consistent with well-established demographic patterns in help-seeking and mental health service use. Results provide initial support for the AMHSS as a brief measure of mental health service use that could be administered in surveillance surveys to adolescents, with the goal of improving services access.