Reducing CO2 emissions in construction is essential due to the significant energy consumption and emissions associated with materials like reinforced concrete. This study aims to optimize foundation systems for high-rise buildings to minimize material use and energy consumption while ensuring stability, serviceability, and durability. A sustainable approach involves the adoption of a Combined Pile-Raft Foundation (CPRF), which optimally integrates the bearing capacities of both the raft and piles, offering an efficient alternative to conventional Pile Group Foundations (PGF). Three-dimensional nonlinear analyses utilizing the Finite Element Method (FEM) were performed in Plaxis 3D to optimize the design and performance of the CPRF system. The study evaluates the investigation of pile length, pile spacing, and pile diameter to assess CPRF performance. Results demonstrate that CPRF enhances load-bearing capacity and reduces the amount of concrete required to resist that load resulting in less emission of CO2. This research highlights CPRF’s potential to achieve sustainable, resilient infrastructure, providing valuable insights for geotechnical designers.