["Journal of Consumer Behaviour, Volume 25, Issue 2, Page 651-675, March 2026. ", "\nABSTRACT\nDefaults have emerged as a ubiquitous and powerful nudging tool, attracting considerable research scrutiny in the field of consumer behavior. Default refers to the alternative the consumer receives unless he/she explicitly requests otherwise. This Systematic Literature Review (SLR) focuses on the power of defaults on consumer choice. A domain‐based systematic review is employed to analyze 61 peer‐reviewed articles from Scopus, Web of Science and manual search, published between 2000 and 2025. Drawing on the Theory–Context–Construct–Method (TCCM) framework, this paper presents an up‐to‐date synthesis of research, while setting the future research agenda. The opt‐out engages higher levels of consumer consent but its superiority can be contingent on specific contextual factors. Building on the assertion that “one default does not fit all” we identify conditions that may lessen or reverse default effects. Notably, opt‐in and active choice seem more effective in engaging a more permanent consent. The paper examines the underlying mechanisms, contextual factors, carry‐over effects and ethical considerations. The prospect theory and self‐determination theory serve as the theoretical foundations of default research. Finally, the paper aims at setting the future research agenda by highlighting equivocal findings, areas with limited research attention, and issues that would enhance the effectiveness of defaults in promoting consumer welfare.\n"]