Waste leakage has become a major global concern due to the negative impacts on aquatic ecosystems and human health. By contrasting baseline with mitigation scenarios, our study combines spatial analysis with the Shared Socioeconomic Pathways storylines to develop plausible future waste leakage mitigation strategies up to 2040. Our study indicates that the leakage of MSW to the aquatic environments is highly dependent on population size, populated area (urban – rural), physical environment presence, length and area of aquatic systems, waste generation and composition, and level of waste management systems. We found that not necessarily countries exhibiting the highest amounts of uncollected waste coincide with countries having the highest waste leakage in the aquatic environments. The results show that the adoption of circular waste management systems would be an active mitigation strategy that could stop waste from entering the aquatic ecosystems in the first place. However, even in a scenario representing a sustainable world in which technical, social, and financial barriers are overcome and public awareness and participation to reduce, reuse and recycling waste exists, it would be impossible to mitigate and eliminate waste leakage before 2030. This translates into a failure to meet the waste-related Sustainable Development Goals.