Climate change is a serious threat to the future ecological environment, and household behaviors contribute significantly to greenhouse gas emissions. Engaging young people in sustainable household...Show moreClimate change is a serious threat to the future ecological environment, and household behaviors contribute significantly to greenhouse gas emissions. Engaging young people in sustainable household behaviors is crucial to reduce their carbon footprints. Therefore, this study aimed to investigate whether young adults’ perceived need for autonomy, relatedness, and competence vary across different living situations (Deci & Ryan, 2000) and if these needs, in turn, promote their motivation to perform pro-environmental behavior (PEB). The hypothesis was that students living in peer co-residentials experience higher levels of these needs, leading to increased PEB. Methods: This observational and cross-sectional study was part of the Horizons research project. The participants included students (N = 214), aged 16 to 26. The Needs-satisfaction Scale (Sheldon et al., 2001) was used to measure perceived autonomy, relatedness and competence for PEB. A modified version of the Behavior-based Environmental Attitude Scale for adolescents (Kaiser et al., 2007) was used to assess PEB. Living situations were categorized as peer co-residentials, parental homes, and other households. One-way ANOVAs were performed to analyse the levels of the needs across the household types. A between-subject ANCOVA was performed to analyse the main effects of household, autonomy, relatedness and competence on PEB, including interaction effects. Results: No significant differences were found in the levels of perceived needs across the household types, p >. 05. Similarly, no main effects on PEB were identified, p >. 05. However, a significant interaction effect between perceived competence and household type on PEB was observed, F(3, 204) = 4.55, p < .001. Regression analysis revealed an interaction between perceived competence and PEB within in parental households, F(1, 74) = 4.39, p = .04, with competence having a significant and positive effect on PEB, b = .77, t(75) = 2.09, p < .001. Conclusion: Within parental homes, students who perceived more competence while performing PEB were more inclined to engage in PEB. Except for this effect, the findings revealed no significant differences in perceived needs or levels of PEB across household types. This study highlights that young adults’ perceived competence in parental homes plays a role in their environmental engagement. Future research may explore how parent-child relationships continue to shape young adult’s perceived needs after they move out. Understanding these dynamics can inform programs aimed at engaging young adults’ pro-environmental behavior, leading to reduced household carbon footprints over time.Show less