A decision support framework was developed to identify the economic, social, and ecological costs and benefits of plastic pollution interventions for different sectors and stakeholders. The net cost as a function of six cost and benefit categories was calculated with the following equation: cost of implementing an intervention (direct, indirect, and nonmonetary costs) minus recovered costs and benefits (monetary and nonmonetary) produced by the interventions. The framework was applied to two quantitative case studies (a solid waste management plan and a trash interceptor) and four comparative case studies, evaluating the costs of beach cleanups and waste-to-energy plants in various contexts, to identify factors that influence the costs of plastic pollution interventions. The socioeconomic context of implementation, the spatial scale of implementation, and the time scale of evaluation all influence costs and the distribution of costs across stakeholders. The framework provides an approach to estimate and compare the costs of a range of interventions across sociopolitical and economic contexts.