As horizontal model resolution increases, hydrological processes, such as lateral subsurface flow, need to be explicitly represented and parameterized. In this study, we investigate the sensitivity of the simulated discharge of the distributed hydrological model wflow_sbm to the lateral saturated hydraulic conductivity over many catchments in England, Scotland and Wales. The high quality CEH GEAR rainfall and CAMELS-GB dataset make it possible to get insight into the spatial variability of the horizontal-to-vertical saturated hydraulic conductivity ratio (i.e. anisotropy) and its effect on simulated discharge. Wflow_sbm models, including forcing (both EOBS and CEH GEAR), were automatically set up using reproducible workflows for each CAMELS-GB basins. The anisotropy of the lateral hydraulic conductivity was varied over a large range (1 – 10000) and performance was assessed using the non-parameteric KGE metric focusing on recession and baseflow performance. Wflow_sbm model results indicate a high sensitivity to the anistropy of the hydraulic conductivity. When plotting the optimal anistropy values and resulting lateral hydraulic conductivities across England and Wales, clear patterns emerge that seem to coincide with geological features. For the best performimg anistropy values, we obtain high KGE values (median=0.84). Resulting best performing lateral saturated hydraulic conductivity values seem realistic when compared with literature values. When comparing results to simulations from a tuned Grid2Grid model, the wflow_sbm model shows comparable performance for most stations. However, for parts in the south of England, where chalk in the subsoil highly influences infiltration and lateral flow behaviour, the performance of wflow_sbm is less good. This is likely caused by the used geofabric which limits the soil depth often to 30 – 60 cm while it is known that the chalk layers below the soil are also hydrologically active and exclusion of anthropogenic water use in the model setup which is known to have a pronounced influence in these regions. Spearman rank correlation of the logarithm of the derived lateral hydraulic conductivities against derived base recession coefficients from literature results in a correlation of -0.56 indicating a moderate to strong negative relationship. This analysis is a first step towards getting more insight into parametrization of lateral saturated conductivity and results will be used to investigate deriving transfer function(s) for this parameter in the near future.