A meta-analysis of the real-world impact of sustainability labeling on consumer choices

Sustainability labeling aims to encourage consumers toward environmentally friendly choices, yet its effectiveness remains uncertain. In this pre-registered meta-analysis of 49 studies (n = 150,221 participants), we assess the impact of sustainability labeling on observable consumer behaviors. Before adjusting for publication bias, labeling shows a small-to-moderate effect (d = 0.25; 95% CI: [0.17, 0.32]) that is stronger online (d = 0.31; [0.22, 0.40]) than offline (d = 0.07; [0.01, 0.13]). After correcting for publication bias, the effects substantially diminish overall (d = 0.13; [0.05, 0.22]) and online (d = 0.20; [0.10, 0.30]), and become negligible offline (d = 0.05; [-0.07, 0.16]). Thus, current evidence likely overstates the behavioral impact of sustainability labeling, particularly in physical retail contexts. Although labeling may indirectly influence long-term behaviors and institutional purchasing decisions, more ambitious initiatives are required to meaningfully shift consumer behaviors toward sustainability at scale.