Research has indicated that sexual minority women (SMW) drink more than do their heterosexual counterparts. Minority stress theory postulates that this increased drinking is motivated by efforts to modulate distress related to minority status, highlighting the potential importance of coping and enhancement drinking motives. Social learning theory postulates that SMW are motivated to drink more because their social companions model drinking behavior and convey social norms regarding appropriate alcohol consumption, suggesting that socialization and conformity motives may be important. The degree to which different motives for drinking affect SMW’s alcohol consumption may depend in part on whether SMW drink with other sexual minorities, but this has not been investigated. This study examined daily data across 2 separate 14-day bursts to understand associations among daily drinking motives, the sexual identity of drinking companions, and alcohol consumption among 67 young SMW who reported on 553 social drinking days. On days when SMW had higher than typical socialization and enhancement motives, they tended to drink more, and SMW who typically had higher coping motives tended to drink more on any given day. Further, higher than typical enhancement motives were associated with heavier drinking on days when SMW drank with only heterosexual companions, relative to days when they drank with only sexual minority companions or in mixed sexual-identity groups. SMW’s typical conformity motives were more strongly related to drinking on days when SMW drank in mixed sexual-identity groups relative to heterosexual companions only. These results indicate that SMW’s drinking motives and drinking companions may be important targets for future research and intervention.