Background: Conceptualizations of health have expanded to include indicators of adolescents' physical and mental wellness, rather than solely the absence of diseases or disorders. Although extensive research has identified links between mental and physical wellness, few studies have investigated the relationship between health promotion and happiness, particularly in adolescent populations who may be at particular risk for engaging in health-compromising behaviors, such as alcohol consumption. Methods: This cross-sectional study examined the relationship between 12 health-promoting behaviors and subjective well-being in a sample of 450 high school students from 2 states. Participants reported on their diet, physical activity, sleep hygiene habits, as well as abstinence from tobacco and alcohol products, and completed a multidimensional assessment of subjective well-being. Results: Findings demonstrated that 7 of the 12 health-promoting behaviors were significantly correlated with adolescents' subjective well-being. A sizeable portion of the variance in adolescents' subjective well-being (39.8%) was accounted for by the linear combination of the 12 health-promoting behaviors of interest. Increased physical activity, sleep hygiene cognitive/emotional factors, and bedtime routine all were identified as unique predictors of subjective well-being. Conclusions: These findings bring attention to the salience of daily physical activity and sleep hygiene and their associations with adolescents' happiness.