Abstract. Soil moisture (θ) impacts the climate system by regulating incoming energy into outgoing evapotranspiration (ET) and sensible heat flux components. Therefore, investigating the coupling strength between θ and ET is important for the study of land surface/atmosphere interactions. Here, we use in-situ AmeriFlux observations to evaluate θ/ET coupling strength estimates acquired from multiple land surface models (LSMs). For maximum robustness, coupling strength is represented using the sampled normalized mutual information (NMI) between θ estimates acquired at various vertical depths and surface flux represented by fraction of potential evapotranspiration (fPET, the ratio of ET to potential ET). Results indicate that LSMs are generally in agreement with AmeriFlux measurements in that surface soil moisture (θ_S) contains slightly more NMI with fPET than vertically integrated soil moisture (θ_V). Overall, LSMs adequately capture variations in NMI between fPET and θ estimates acquired at various vertical depths. However, one model – the Global Land Evaporation Amsterdam Model (GLEAM) – significantly overestimates the NMI between θ and ET and the relative contribution of θ_S to total ET. This bias appears attributable to differences in GLEAM's ET estimation scheme relative to the other two LSMs considered here (i.e., the Noah with Multi–parameterization option and the Catchment Land Surface Model). These results provide insight into improved LSM model structure and parameter optimization for land surface-atmosphere coupling analyses.