This is the modelled basal melt rates in six experiments using different geothermal heat flux (GHF) maps as forcing for an offline coupling between a forward model and an inverse model. The forward model consists of a thermomechanical steady state model using an improved shallow ice approximation in equilibrium with the subglacial hydrological system. The inverse model is solved using 3D full Stokes model. The six GHF maps are from Martos et al. (2017), Shen et al. (2020), An et al. (2015), Shapiro and Ritzwoller (2004), Purucker (2012) and Li et al. (2021). Each filename includes the family name of the first author of the GHF map that is used. For instance, basal_meltrate_an.nc provides the modelled basal melt rates using An et al. (2015) GHF. Files are provided in netcdf format. The netcdf files have 2D grids only. The unit of modelled basal melt rate is mm/yr. The value outside our modelled domain is given as 9.96921e36. The positive value inside our modelled domain represents basal melt rate, while negative represents basal freeze rate. For more information, please see the following paper that is currently accepted by The Cryosphere: H. Kang et al.: Evaluation of six geothermal heat flux maps for the Antarctic Lambert–Amery glacial system, The Cryosphere, 2022.