This study sought to determine whether drinking limit goal commitment and goal confidence mediate the association between desire to get drunk and binge drinking (4+ drinks for a woman and 5+ drinks for a man on a given occasion) among young adults exposed to text message goal-related feedback. Participants were 297 young adults with hazardous drinking randomized to one of two text-message interventions incorporating drinking limit goal-related assessments and feedback who also completed at least two days of assessments over 12 weeks of intervention exposure. On the two days per week they typically drank alcohol, participants were asked to report plans to drink (yes/no). If a drinking plan was endorsed, participants reported desire to get drunk (0 [not at all] to 8 [completely]), willingness to commit to a drinking limit goal (yes/no), and (contingent on goal commitment) goal confidence (0 [not at all] to 8 [completely]). The next day, participants reported drinking quantity, coded as a binge drinking day (yes/no). Mediation was tested using path models of simultaneous between- and within-person effects using Maximum Likelihood. At both within- and between-person levels, we found significant indirect path effects of goal commitment and goal confidence between desire to get drunk and binge drinking. Greater than usual desire to get drunk was associated with lower drinking limit goal commitment and confidence, whereas greater than usual goal commitment and confidence were associated with lower likelihood of same day binge drinking. Findings support a mechanistic model where contextual variations in same day drinking limit goal commitment and confidence mitigate the path between desire to get drunk and binge drinking among young adults. Employing just-in-time strategies to reinforce drinking limit goal commitment and goal confidence could reduce hazardous drinking and related harms.