Ethical consumer behaviour has been receiving much attention in recent times, due to heightened social issue on
sustainability, corporate social responsibility and ethical consumption from the community. Integrated with the
Value-Belief-Norm (VBN) Theory, this study investigates the influences of altruistic, biospheric, and hedonic
values on ethical buying behaviour under the mediating mechanism of behavioural beliefs, personal norms, and
subjective norms. Moreover, the present research also explores the moderating effects of perceived product
quality and social stigma in the relationship between subjective norms, personal norms and ethical buying
behaviour. A cross-sectional survey design approach was employed where data were gathered from students
studying in India. The findings indicate that altruistic, biospheric, and hedonic values have an indirect impact on
ethical buying behaviour via related behavioural beliefs, personal norms, and subjective norms. The moderating
roles of quality and stigma show some interesting counteracting influences. Product quality was found to
enhance the subjective norms and ethical buying behaviour relationship while undermining the relationship
between personal norms and ethical buying behaviour. By contrast, stigma reduced the influence of subjective
norms but enhanced the effect of personal norms on ethical buying behaviour. The work adds to the ethical
consumption literature by combining theoretical perspectives and emphasising the complexity of how these
moderating variables function in ethical decision-making. The findings provide both theoretical implications
from the perspective of the psychological mechanism of ethical behaviour and managerial implications for firms
looking to motivate ethical consumption.