In this section, we use the S66 data set to examine how the choice of basis impacts the accuracy of the DLPNO approximation. Error statistics for counterpoise-corrected S66 interactions energies at the RI-MP2 level are summarized in Table , where "error" is defined with respect to the canonical RI-MP2 result. A significant amount of additional S66 data can be found in Section S1 of the Supplementary Material, including individual DLPNO errors for each S66 dimer; see Figs. S1 and S2 for Dunning basis sets and Figs. and for Karlsruhe basis sets. As discussed in Section II C, we examine both the loose/normal/tight thresholds as typically defined for MP2 calculations, and also the more aggressive thresholds that are defined for CCSD(T) calculations. (See Table for the numerical thresholds.) This allows us to gain some insight into how these results may bear on CCSD(T) calculations.