The total ionic conductivity κ as a function of slit height H is provided in the left panel of Fig. . We observe that the largest slit studied, H = 17.29 Å, exhibits 11% lower conductivity than the bulk electrolyte, with a further decrease in the conductivity upon confining the electrolyte to a bilayer and monolayer (H = 9.25 Å and H = 6.83 Å, respectively). The magnitude of this decrease in conductivity is comparable to what would be expected based on the limited experimental data available for systems such as this: Esfandiar et al. characterized aqueous NaCl transport in bilayer electrolytes confined to slit pores fabricated by van der Waals assembly, observing a 32% decrease in ionic conductivity relative to a bulk electrolyte. We observe a 35% decrease in our bilayer system, albeit at a higher concentration than was used by Esfandiar et al. distinct , L -- distinct , and L +-. In each panel, the rightmost data point corresponds to the bulk electrolyte. Note that while the legend denotes each L ij , the plotted data corresponds to e 2 L ij such that the units are mS/cm. Error bars are given as the standard deviation of five independent replicate simulations.