By changing the OR value used as reference, one can focus on a different type of comparison. For instance, by using the (best estimate) CBS OR value within each gauge for a given method as reference, once can probe the basis set convergence of each choice of gauge. If the CBS OR value for a specific choice of gauge is used as reference, one can test gauge invariance for a given method as a function of the basis set size. Finally, by using the CBS OR value for a specific choice of gauge and method, one can compare differences between methods. For each molecule in the test set, we selected the enantiomer with positive OR (when calculated with the largest basis set) to avoid complications in the interpretation of the sign of ∆ ref i in Eq. 9; thus, ∆ ref i < 0 always indicates an underestimation of the reference value and vice versa. The molecules for which we changed enantiomer compared to the original study are also listed in the SI. The OR signs are consistent for all molecules and basis sets, with a few exceptions with aug-cc-pVDZ that are explicitly discussed in the next section.