Small-strain stiffness is seen as a fundamental property that almost all soils ranging from colloids to gravels, and even rocks exhibit. This is the case for static and dynamic loading, and for drained and undrained conditions. In literature, small-strain stiffness is assumed to exist due to inter-particle forces within the soil skeleton. Therefore, it can be altered only if these inter-particle forces are rearranged (Benz et al., 2009). The deformation behaviour as a result of the excavation of a building pit in the inner city of Amsterdam is studied using the small strain stiffness model in PLAXIS 2D. The numerical results of deformations on the sheet pile wall during the different excavation stages obtained using PLAXIS are compared with the measured data. The objective of this study is to investigate the differences in computed deformation of the sheet pile wall when using the Hardening Soil Model (HS) and the Hardening Soil Small Strain Stiffness model (HSsmall) employing the correlations of Alpan (1970) and Benz & Vermeer (2007) compared with the inclinometer data to assess their performance in an actual design process.