It has been recognized that quantum‐chemical predictions of dispersive (nonresonant) chiroptical phenomena are exquisitely sensitive to the periphery of the electronic wavefunction. To further elaborate and potentially exploit this assertion, linear‐response calculations of specific optical rotation were performed within the framework of density‐functional theory (DFT) by augmenting small basis sets (e.g., STO ‐ 3G and 3 ‐ 21G) for the core and valence electrons with diffuse functions taken from substantially larger bases (e.g., aug‐cc‐pVXZ where X = D, T, or Q). Of particular interest was the ability of such computationally efficient (augmented small‐basis) model chemistries to reproduce results derived from more expensive (canonical large‐basis) schemes. The results appear to be quite promising, with the augmented minimal‐basis ansatz often yielding wavelength‐resolved rotatory powers close to those deduced from standard DFT(B3LYP)/aug‐cc‐pVXZ treatments. Analogous linear‐response analyses were performed by means of coupled‐cluster singles and doubles (CCSD) theory, once again leading to augmented small‐basis estimates of specific rotation in reasonable accord with their large‐basis counterparts. Although CCSD predictions were deemed to be slightly worse than those obtained from DFT, they still were of sufficient quality for such reduced‐basis calculations to be considered viable for exploratory work. Chirality 25:606–616, 2013. © 2013 Wiley Periodicals, Inc.