Childhood adversity is associated with exaggerated threat processing and earlier alcohol use initiation. Conclusive links remain elusive, as childhood adversity typically co-occurs with detrimental socioeconomic factors, and its impact is likely moderated by biological sex. To unravel the complex relationships among childhood adversity, sex, threat estimation, and alcohol use initiation, we exposed female and male Long-Evans rats to early adolescent adversity (EAA). In adulthood, >50 days following the last adverse experience, threat estimation was assessed using a novel fear discrimination procedure in which cues predict a unique probability of footshock: danger (p = 1.00), uncertainty (p = .25), and safety (p = .00). Alcohol use initiation was assessed using voluntary access to 20% ethanol, >90 days following the last adverse experience. During development, EAA slowed body weight gain in both females and males. In adulthood, EAA selectively inflated female threat estimation, exaggerating fear to uncertainty and safety, but promoted alcohol use initiation across sexes. Meaningful relationships between threat estimation and alcohol use initiation were not observed, underscoring the independent effects of EAA. Results isolate the contribution of EAA to adult threat estimation, alcohol use initiation, and reveal moderation by biological sex. (PsycINFO Database Record