This study presents projections of global mismanaged plastic waste (MPW) generation from 2015 to 2060 at a 1 km resolution. Using country-level waste management data, population, and GDP projections, the authors estimate that global MPW production was between 60 and 99 million metric tonnes (Mt) in 2015. Under a business-as-usual scenario, this could triple to 155–265 Mt by 2060. The majority of MPW (91%) is transported via watersheds larger than 100 km², suggesting rivers are major pathways for plastic litter to the ocean. The study highlights that African and Asian continents will continue to have disproportionately high MPW loads. However, significant investment in waste management infrastructure and international efforts to reduce plastic in municipal solid waste could reduce this growth. The results show that plastic waste generation is spatially heterogeneous, with high concentrations in urban areas and near transportation axes. The study also finds that the fraction of plastic in municipal solid waste is generally independent of per capita GDP. Future projections indicate that global MPW generation could reach 380 Mt by 2060 under a business-as-usual scenario. However, with improved waste management and reduced plastic use, MPW generation could be reduced to a third of current levels. The study emphasizes the need for international cooperation to manage plastic waste, as current trends could lead to twice the current amount of MPW generation by mid-century. The results also highlight the importance of improving waste management infrastructure and reducing plastic use to mitigate the environmental impact of plastic waste.This study presents projections of global mismanaged plastic waste (MPW) generation from 2015 to 2060 at a 1 km resolution. Using country-level waste management data, population, and GDP projections, the authors estimate that global MPW production was between 60 and 99 million metric tonnes (Mt) in 2015. Under a business-as-usual scenario, this could triple to 155–265 Mt by 2060. The majority of MPW (91%) is transported via watersheds larger than 100 km², suggesting rivers are major pathways for plastic litter to the ocean. The study highlights that African and Asian continents will continue to have disproportionately high MPW loads. However, significant investment in waste management infrastructure and international efforts to reduce plastic in municipal solid waste could reduce this growth. The results show that plastic waste generation is spatially heterogeneous, with high concentrations in urban areas and near transportation axes. The study also finds that the fraction of plastic in municipal solid waste is generally independent of per capita GDP. Future projections indicate that global MPW generation could reach 380 Mt by 2060 under a business-as-usual scenario. However, with improved waste management and reduced plastic use, MPW generation could be reduced to a third of current levels. The study emphasizes the need for international cooperation to manage plastic waste, as current trends could lead to twice the current amount of MPW generation by mid-century. The results also highlight the importance of improving waste management infrastructure and reducing plastic use to mitigate the environmental impact of plastic waste.