Sustainable consumption is widely recognized as a response to environmental challenges, yet a persistent value–action gap limits the translation of pro-environmental values into actual purchasing behavior. This study examined the determinants of the value–action gap in green consumption among Generation Z (Gen Z) professionals in Lipa City, Batangas, focusing on the effects of green consumption values (GCV) on green purchase behavior (GPB) and the role of general risk aversion (GRA) and green subjective knowledge (GSK). Guided by the Theory of Planned Behavior and value-based environmental theories, the study adopted a causal-descriptive and quantitative research design. Data was collected from 119 Gen Z professionals aged 21–28 using structured questionnaire from Essiz et al. (2023). The data collected was analyzed with the use of descriptive statistics and moderation multiple analysis. The results showed that green consumption values and green subjective knowledge both significantly influence green purchase behaviors, suggesting that individuals who value the environment and have a better understanding of sustainability are more likely to engage in eco-friendly purchasing. On the other hand, green risk aversion did not have a significant effect, indicating that concerns about risk do not strongly influence green purchase behaviors. In addition, the moderating effects of green subjective knowledge and green risk aversion were not significant, which means that the impact of green consumption values on behavior remains consistent regardless of differences in knowledge or risk tendencies. This study contributes localized evidence to sustainable consumption research in emerging economies and supports Sustainable Development Goal 12.