Abstract In this study, the Hydrologic Evaluation of Landfill Performance (HELP3.8D) model was developed to evaluate the spatiotemporal distribution of potential groundwater recharge (GWR) in Tasuj aquifer, northwestern Iran. High-resolution future climatic data from second-generation Canadian Earth System Model (CanESM2) general circulation models (GCMs) was produced under different scenarios of Representative Concentration Pathways (RCP2.6, RCP4.5, and RCP8.5). The analysis of climate parameters demonstrated that under RCP2.6, climatic variation will be substantially similar to that of the observed period (1961–2005), while moderate and severe droughts are anticipated under scenarios RCP4.5 and RCP8.5, respectively, over 2017–2030. The projection results showed that GWR will be altered by climate change, on average, from 31 mm/year at baseline to 32 (+3%), 28.5 (−8%) and 11.5 (−63%) mm/year under the RCP2.6, RCP4.5 and RCP8.5 scenarios, respectively. This approach can be easily replicated by other researchers and could be beneficial for monitoring water security and managing groundwater resources in other catchment areas.