•LCA carried out for plastic waste recycling/recovery options in Singapore.•Combination of options considered capacities and sizes of recycling plants available.•Total of 8 scenarios were compared for 822,200 tonnes of plastic waste.•Waste options included mechanical recycling, pyrolysis and gasification.•Normalization and weighted scores done to select best option. In Singapore, 822,200 tonnes of plastic waste was generated in 2016, with only 7% recycled. Due to the complex nature of plastic waste mixtures, mechanical recycling is often inefficient, leading to a majority of waste being incinerated. In this article, alternative solutions are introduced to address the waste problem, such as recovering valuable fuels from plastics via thermochemical methods. Life cycle assessment (LCA) was adopted to investigate 8 scenarios of plastic waste management options. In a nation with land scarcity, the scales and sizes of each plastic waste recycling/recovery method is also taken into consideration. The results demonstrated how different combinations of four plastics valorization technologies, and associated capacities, affected the potential environmental benefits and drawbacks of plastic waste treatment systems. In order to enable selecting the best option among the 8 scenarios, normalization and weighting was carried out.