A primary objective of foreign aid in conflict zones is to help political actors win citizens’ ‘hearts and minds’. Previous studies have focused on assistance provided to state actors; however, this article examines aid's impact on rebel governance. It argues that aid only bolsters opinions of rebel governors where military control is uncontested. In contested areas, rebels lose credibility if they cannot offer protection, and they have difficulty delivering – and receiving credit for – services in insecure environments crowded with competitors. Using novel data from the Syrian civil war, this article shows that aid improves opinions of opposition councils in uncontested areas but not in communities experiencing intra-rebel conflict. It also explores the underlying mechanisms using in-depth interviews with residents of Aleppo City and Saraqeb. The findings reveal a more nuanced relationship among aid, military competition and governance than prior studies have suggested, which has implications for both scholars and policy makers.