In recent times, there has been a notable increase in the demand of high-rise buildings. Pile raft foundation has been recognized as the most economical and efficient foundation for high-rise buildings. By using pile raft foundations, the risk of sudden collapse in these buildings is also mitigated. Moreover, both total and differential settlement are decreased compared to traditional pile group and unpiled raft foundations. However, in practical designs, the contribution of the raft is often disregarded and the foundation is typically designed solely as a pile foundation. Therefore, the present study aims to determine the CPRF coefficient of a pile raft subjected to axial load. Further parametric study is performed to examine the effect of pile diameter on the response of pile raft. Piles share maximum proportion of axial load. With increase in pile diameter CPRF coefficient of pile increases and that of raft decreases. Also, settlement of pile raft decreases with increase in pile diameter.