Objective: Language brokering occurs frequently in immigrant families and can have significant implications for the well-being of family members involved. The present study aimed to develop and validate a measure that can be used to assess multiple dimensions of subjective language brokering experiences among Mexican American adolescents. Method: Participants were 557 adolescent language brokers (54.2% female, Mage.wave1 = 12.96, SD = .94) in Mexican American families. Results: Using exploratory and confirmatory factor analyses, we were able to identify 7 reliable subscales of language brokering: linguistic benefits, socioemotional benefits, efficacy, positive parent–child relationships, parental dependence, negative feelings, and centrality. Tests of factorial invariance show that these subscales demonstrate, at minimum, partial strict invariance across time and across experiences of translating for mothers and fathers, and in most cases, also across adolescent gender, nativity, and translation frequency. Thus, in general, the means of the subscales and the relations among the subscales with other variables can be compared across these different occasions and groups. Tests of criterion-related validity demonstrated that these subscales correlated, concurrently and longitudinally, with parental warmth and hostility, parent–child alienation, adolescent family obligation, depressive symptoms, resilience, and life meaning. Conclusion: This reliable and valid subjective language brokering experiences scale will be helpful for gaining a better understanding of adolescents’ language brokering experiences with their mothers and fathers, and how such experiences may influence their development.