Further speedups can be obtained by exploiting separability of the SAPT energy decomposition to evaluate different energy components at different levels of theory. A preliminary version of this idea, which is trivial to implement, is to use a smaller basis set to evaluate δE HF , the correction for induction effects beyond second-order perturbation theory. We find that a minimally-augmented double-ζ basis, such as 6-31+G(d) or def2-ma-SVP (the latter of which is introduced as part of the present work) is sufficient to evaluate δE HF , which is defined by energy difference and thus converges rapidly. For quadruple-ζ calculations, this mixed-basis procedure affords speedups of 3-4×.