Consumers’ capabilities, opportunities and motivations that drive single-use plastic (SUP) reduction: a qualitative study on the case of milk packaging

Purpose The purpose of this study is to identify enablers and barriers influencing single-use plastic (SUP) milk bottle volume reduction in New Zealand using the Capability–Opportunity–Motivation–Behaviour (COM-B) theory. Single-use plastic (SUP) milk bottles contribute significantly to plastic waste, yet when compared to other types of single-use plastic packaging (e.g. plastic bags), they have received far less research attention. Design/methodology/approach The study conducted in-depth interviews with 20 milk consumers in New Zealand, thoroughly analyzed via reflexive thematic analysis in NVivo 14. Findings Findings reveals key drivers of change, including heightened awareness of plastic waste, concerns over plastic-related health risks and recognition of recycling limitations. However, significant barriers persist, such as cost constraints, the market dominance of milk plastic packaging, limited reusable milk alternatives and insufficient policy support. Many participants indicated that high prices and low availability of reusable milk options impede broader adoption. Practical implications By applying the COM-B model, the study offers deeper insights into how individual and systemic factors intersect, revealing key strategic guidance for policymakers, producers, retailers and environmental advocates seeking to transform the dairy supply chain for circular economy objectives. This study emphasizes the need for holistic, multi-level interventions, policy development, enhanced retail infrastructure and behaviour change, to foster a shift toward sustainable and cost-effective sustainable packaging. Originality/value This is the first study to explore consumers’ barriers and enablers to reduce milk plastic packaging. The findings of this study add to the existing literature on plastic reduction and behaviour change.