This article examines the attitude–behaviour gap in sustainable consumption among young adults in Poland, focusing on the psychological and contextual mechanisms that hinder the translation of pro-environmental attitudes into everyday practices. The findings show that declared support for sustainable solutions does not translate into behaviour when decision costs are elevated, particularly in terms of price, limited availability of green alternatives and low label readability. Drawing on six focus group interviews and reflexive thematic analysis, this study identifies the dominance of transactional over normative factors, a reliance on simple heuristics (e.g., packaging material) rather than verified certifications, and the central role of habit and convenience in consumption choices. Interpreting these results through the Theory of Planned Behaviour, the analysis shows how price- and supply-related barriers reduce perceived behavioural control and undermine sustainable decision making. This article contributes to behavioural research on sustainable consumption by identifying key mechanisms underlying the attitude–behaviour gap in a Central and Eastern European context. Practical implications include simplifying environmental labels, low-cognitive-load consumer education and interventions that increase the accessibility and visibility of sustainable options. Limitations stem from the qualitative design and the urban profile of the sample, suggesting cautious generalisation and the need for replication using diverse populations and methodological triangulation.
Pilch et al. (Sat,) studied this question.