The construction sector accounts for 39% of global carbon emissions, so global attempts are being made to decarbonize this sector. Geosynthetics is one such field, traditionally utilizing polymeric resins, which are neither energy-efficient nor sustainable. Herein, Coir geotextile (CGT) is considered an ideal green geosynthetic. Comparative studies of natural fibers under-line their relative advantages. Coir Fiber (CF) is composed of lignocellulosic material that imparts strength, durability, and ductility while keeping it sustainable and economical. Its role is suitable for low-cost construction applications, including strengthening soil subgrade. This paper has reviewed the existing scholarship to examine the soil-coir geotextile interactions. Experimental investigations suggest that the subgrade's dry density, shear strength, and CBR increase noticeably while moisture, settlement, and plastic deformation decline with CGT reinforcement. This study suggests geotextile placement above the subgrade, which aids soil consolidation while reducing pavement thickness due to enhanced subgrade characteristics.