Energy consumption has been identified as the key contributor to carbon dioxide emissions and the depletion of natural resources. Promoting the purchase of energy-efficient appliances is crucial for environmental sustainability. While numerous studies have explored consumer purchase decisions regarding energy-efficient appliances, the literature remains broad and fragmented. Anchoring in the Theory–Context–Characteristics–Methods (TCCM) framework, this systematic literature review aims to synthesize the available research and offer a complete overview of the current state of research into consumer purchases of energy-efficient appliances. Conducting a thorough analysis of 142 empirical studies, this study uncovers that the Theory of Planned Behavior is the most frequently used framework, and most studies adopted quantitative methods and focused on emerging Asian countries (e.g., China, Pakistan, and Malaysia). In addition, this study also points out socio-demographic, psychographic, situational, and marketing-related factors that affect consumer purchase behavior toward energy-efficient appliances. Based on these findings, this study proposes a research agenda for scholars to advance the research field and practical implications for policymakers, manufacturers, and marketers to encourage the adoption and purchase of energy-efficient products.