We need to reduce household food waste, but the complexity of its determinants makes this difficult. Here we put forward a model for understanding some of the key behavioural and psychological drivers thought to promote or undermine food waste reduction. The model draws on multiple theories and integrates reflective processes (e.g., the influence of goals and outcome expectancies on planning behaviours) with automatic processes (e.g., habitual behaviours), psychological traits (e.g., self-efficacy and disgust sensitivity) and environmental influences (e.g., stress and time pressure). It leads us to identify two important potential levers for change: promoting shorter term, flexible meal planning and changing the way we feel about food waste.