BACKGROUND: The potential heterogeneity in daily smoking across young adulthood has been relatively understudied. Relatedly, the unique and joint associations of earlier risk factors with young adults' daily smoking largely remain unknown. To address these gaps, this work identified subgroups of daily smoking trajectories during young adulthood and linked them to earlier attention problems and smoking-specific and general family context. METHODS: Data came from the Seattle Social Development Project, a longitudinal study following a community sample (N = 808). Participants' daily smoking was measured from ages 21-33. Earlier attention problems were assessed at ages 14-16 and 18. Earlier smoking-specific and general family factors were assessed at ages 10-16 and 18. RESULTS: Growth mixture models produced four profiles: chronic daily smokers, increasers, decreasers, and no-daily smokers. Results from multinomial logistic regressions revealed that earlier attention problems and smoking-specific family factors may contribute to daily smoking in the early 20 s, whereas earlier general family context provided protection for trajectories of daily smoking characterized by changes in the late 20 s and early 30 s DISCUSSION: Selective prevention strategies that expand people's repertoire of healthy options to address attention problems might be helpful, considering the possibility of using tobacco as means to mitigate attention problems. Our findings also highlight the importance of nurturing earlier general family context, a relatively overlooked dimension in smoking prevention efforts, to facilitate young adult smokers' desistence from daily smoking, particularly those who have attention problems in adolescence.