A study on the coagulant activity of plant-based coagulants, Sterculia foetida and Moringa oleifera, which identifies their potential in purifying water to curb the crisis of water shortage in developing and underdeveloped nations. This entails the need of a comparatively cheap and affordable water treatment solution to eliminate the shortcomings of chemical aids such as cost and pH. The experimentation is restricted to laboratory-scale treatment of synthetically prepared kaolin solution in distilled water and tap water of initial turbidity 595 and 844 NTU, respectively, and pH 7.8–7.9 with coagulant dosages between 20–800 mg. A novel work on S. foetida seeds has been presented which is compared with M. oleifera coagulant on the basis of turbidity and pH. The effect of solvents like distilled water, NaCl, and NaOH for active coagulant extraction from seeds is significantly observed on turbidity removal. S. foetida shows up to 97% turbidity reduction when NaCl and NaOH are used and 96% with powder dosages. M. oleifera extracted in NaCl gives a higher turbidity reduction of 97.4% for 20 mg dosage. The coagulants prepared naturally prove to provide a breakthrough in wastewater treatment, and the industrial scale-up could be a pioneer in cost-effective water treatment methods. © 2018 Desalination Publications. All rights reserved.