Roadways play a crucial role in providing maximum transportation services to people around the world. However, in India, with its diverse geography, constructing reliable and safe roadways can be challenging, especially when considering the varying soil strengths in different regions. Kerala, also known as the land of coconut trees, has an abundant supply of coir, making coir geocells a viable option for reinforcement due to their cost-effectiveness and excellent engineering properties. Construction and demolition waste (CDW) is a significant environmental problem due to its large volume and slow decomposition rate. As the availability of virgin aggregate is reducing day by day, a suitable replacement is necessary. This study investigates the behavior of a geocell-reinforced base course layer using various infill materials over a clayey subgrade. A series of monotonic plate load tests were conducted for experimental purposes. This study used two different infill materials, such as natural aggregate and CDW. A commercially available coir geocell with a height of 15 cm was used to reinforce the base course. All the tests were conducted at a base course thickness of 30 cm. Compared to unreinforced cases, the load-bearing capacity of the base course layer increased with the provision of coir geocell reinforcement. CDW was obtained as a superior filler material than natural aggregate in coir geocell. The results indicate that incorporating coir geocell significantly enhances the ultimate bearing capacity (UBC) of the base course materials. When natural aggregate was used, the UBC saw a 36.3% increase, while an improvement of 36.7% was observed with CDW as the base course material. The surface heaving patterns of the pavement layers were also studied, and it was found that the presence of coir geocell helps in reducing the heaves in the base course layer as well as the subgrade.