With the rise of the sharing economy, luxury fashion rental (LFR) services have seen significant growth by providing sustainable consumption options to newcomers in the luxury fashion market. Several studies have analysed consumer motivations for luxury and collaborative consumption; however, limited research has examined consumer behaviour towards LFR, focusing on the collaborative consumption perspective but overlooking the influence of the characteristics and values of luxury fashion products. Therefore, this study seeks to identify consumer motivations for LFR from both the luxury consumption and collaborative consumption perspectives. Specifically, this study aims to: (1) identify motivations for LFR by reviewing the relevant literature; (2) propose a classification of LFR motivations (intrinsic versus extrinsic) by following self-determination theory; and (3) statistically evaluate and confirm said classification. To this end, data were collected from 359 U.S. consumers via an online survey. Subsequently, a second-order confirmatory factor analysis was conducted to confirm the validity of the second-order hierarchical structure. The findings show that intrinsic LFR motivations include hedonic benefits, uniqueness, and sustainability, while extrinsic motivations include economic benefits, social norms, smart shopping, and ego defence. To conclude this paper, theoretical and practical implications are discussed and recommendations for future studies are presented.