Food waste (FW) is a global problem that is receiving increasing attention due to its environmental and economic impacts. Appropriate FW prevention, valorization, and management routes could mitigate or avoid these effects. Life cycle thinking and approaches, such as life cycle costing (LCC), may represent suitable tools to assess the sustainability of these routes. This study analyzes different LCC methodological aspects and approaches to evaluate FW management and valorization routes. A systematic literature review was carried out with a focus on different LCC approaches, their application to food, FW, and waste systems, as well as on specific methodological aspects. The review consisted of three phases: a collection phase, an iterative phase with experts' consultation, and a final literature classification. Journal papers and reports were retrieved from selected databases and search engines. The standardization of LCC methodologies is still in its infancy due to a lack of consensus over definitions and approaches. Research on the life cycle cost of FW is limited and generally focused on FW management, rather than prevention or valorization of specific flows. FW prevention, valorization, and management require a consistent integration of LCC and Life Cycle Assessment (LCA) to avoid tradeoffs between environmental and economic impacts. This entails a proper investigation of methodological differences between attributional and consequential modelling in LCC, especially with regard to functional unit, system boundaries, multi-functionality, included cost, and assessed impacts. Further efforts could also aim at finding the most effective and transparent categorization of costs, in particular when dealing with multiple stakeholders sustaining costs of FW. Interpretation of results from LCC of FW should take into account the effect on larger economic systems. Additional key performance indicators and analytical tools could be included in consequential approaches.

About one third of global edible food is lost or wasted along the supply chain, causing the wastage of embedded natural and economic resources. Life cycle methodologies can be applied to identify sustainable and viable prevention and valorization routes needed to prevent such inefficiencies. However, no systemic approach has been developed so far to guide practitioners and stakeholders. Specifically, the goal and scoping phase (e.g. problem assessed or system function) can be characterized by a large flexibility, and the comparability between food waste scenarios could be not ensured. Within the Horizon2020 project Resource Efficient Food and dRink for the Entire Supply cHain, this study aimed to provide practitioners with guidance on how to combine life cycle assessment and environmental life cycle costing in the context of food waste. Recent literature was reviewed to identify relevant methodological aspects, possible commonly adopted approaches, main differences among studies and standards and protocols, main challenges, and knowledge gaps. Basing on this review, an analytical framework with a set of recommendations was developed encompassing different assessment situations. The framework intends to provide a step by step guidance for food waste practitioners, and it is composed of a preliminary section on study purpose definition, three decision trees-respectively on assessment situation(s), costing approach, and type of study (footprint vs. intervention)-and two sets of recommendations. Recommendations can be applied to all levels of the food waste hierarchy, stating a generic order of preference for handling food chain side flows. This consistent and integrated life cycle approach should ensure a better understanding of the impact of specific interventions, thus supporting informed private and public decision making and promoting the design of sustainable and cost-efficient interventions and a more efficient food supply chains.