Abstract: The construction of transportation infrastructure above soft soil foundation is prevalent in China, making it imperative to establish a prediction method for settlement applicable to deep soft soil foundations. During field monitoring processes, the primary consolidation deformation and creep deformation are both observed as the main consolidation of deep soft soils takes considerable time. Most prediction models for settlement are based on instantaneous loading and do not consider the whole process of nonlinear consolidation. This study considers the whole process of consolidation deformation and introduces a novel curve expression to account for the nonlinearity in one-dimensional consolidation curves at different stages. Both the instantaneous deformation and delayed deformation are treated as nonlinearities, resulting in an extended creep settlement algorithm that offers a practical approach considering the whole consolidation process. To validate its effectiveness, the curve fitting and prediction comparisons are conducted using the monitoring data from the Osaka Kansai International Airport against three commonly used curve fitting methods as the reference benchmarks. The results demonstrate that the extended creep settlement algorithm provides more accurate and reliable predictions for settlements in soft soil foundations.