It is a standard practice in the industry to disregard the bearing action offered by the pile cap during the design of pile foundation. This often leads to an uneconomical and over conservative design, which makes the structure uneconomical and unsustainable. In this case study, the concept of combined piled raft foundations (CPRF) was studied and applied to the pile foundation of a prominent railway bridge in Mumbai, to propose a more economical design for the pile foundation. The existing pile foundation was modelled and analysed using a standard structural engineering software midas Civil, and the effect of soil structure interaction on the pile group was studied. Considering the bearing capacity of the pile cap leads to a notable reduction in the reactions obtained on the piles. Redesigning the pile group for the newer set of reactions, it is found that smaller-diameter piles are adequate. This new design reduces the amount of concrete required for the construction of the pile foundation. The study also does a side-by-side comparison of the amount of concrete used in both the models- One with the bearing effect of the pile cap (soil-structure interaction) considered, and one where it is not considered. The comparison shows that the foundation in which the bearing effect of the pile cap is considered, requires lesser concrete and thus economises the project in terms of cost, material, and carbon emissions.