The objective of this study was to evaluate the composition and nutrient content of various types of commercial fertilisers used in oil palm plantations in Indonesia. The utilisation of non-conforming fertilisers harms soil fertility and health, leading to decreased plant productivity and affecting product quality. Combating non-conforming fertilisers is therefore crucial in supporting the sustainability of oil palm plantations. This research is classified as evaluative, with primary data comprising fertiliser analysis results, interviews, and field observations. Fertiliser samples were obtained from oil palm plantations in eight provinces in Indonesia, namely Central Kalimantan, South Kalimantan, West Kalimantan, East Kalimantan, South Sumatra, West Sumatra, Riau, and North Sumatra. The results demonstrate that the quality of the tested fertilisers can be categorised into three criteria: Original fertilisers, adulterated fertilisers, and counterfeit fertilisers. NPK fertiliser tends to be a target for counterfeiting due to its relatively high price, widespread usage across various agricultural commodities, and ease of imitation with available technology. In conclusion, this comprehensive assessment sheds light on the varying compositions and nutrient content of fertilisers used in oil palm plantations. The findings can assist plantation managers in making informed decisions to enhance overall productivity and sustainability in oil palm cultivation.