From the perspective of predicting unknown Hammett constants, or those for multiply-substituted systems, we have obtained linear scaling relationships between experimental parameters and all computed protocols studied here. Hirshfeld qmdesc Hirshfeld charges evaluated at carbon atoms perform well globally (R 2 = 0.88), while CASCADE chemical shifts perform well (R 2 = 0.84) in predicting σp values. Overall, these observations lead us to conclude that electronic parameterization strategies should carefully consider the impact of location of probe atoms and how partial atomic charges are derived, since we observe a larger impact than from the choice of density functional and basis set used. Our studies were restricted to the computational description of Hammett parameters, however, as archetypal electronic descriptors that have been applied to LFERs across thousands of studies, we suggest that our findings and recommendations should be considered as part of general computational approaches to electronic parameterization.