Employing narrative inquiry, this paper examines how 30 Mexican and Central American young adults (ages 21 to 34) who immigrated without a parent as teenagers—the unaccompanied 1.25 generation— experienced the subjective feeling of adulthood. Structural realities pushed the unaccompanied 1.25 generation into early adult roles, independence, and social responsibility. In many cases, attainment of “adult” roles, independence, and even social responsibility was not followed by the subjective feeling of adulthood. Instead, the feeling of adulthood emerged in gendered ways, was gradual, and resulted from seeing themselves as competent, mature, and capable of thoughtful decision-making. Moreover, in some cases, traumatic events led some to early identification with adult status or disrupted their identification with adulthood. Their experiences support the idea that becoming an adult is an internal process, and raises questions on how independence and social responsibility are experienced by marginalized youth and incorporated into their sense of adulthood.