In this work we have applied modern computational methods to revitalize time-resolved dielectric-loss spectroscopy as a foundational tool for studying the ground and excited-state electronic configuration of molecules in solution. Electromagnetic simulations of the microwave cavity response function and calculation of molecular dipolar relaxation time improve on the accuracy and broad applicability of the technique. We verify our methods by showing agreement with past literature on the model compound N,N-dimethylaminobenzonitrile. Application of TRDL to ([Ir[dF(CF 3 )ppy] 2 (dtbpy)]X), a photocatalyst of great interest in the modern renaissance of light escalated chemistry, reveals dramatic changes in the dipole moment in both ground and excited-states depending on the identity of the counter ion X -. Contact-ion pairing is observed in 1,4-dioxane when X = PF - 6 , and there is a negative change in the dipole moment upon photoexcitation. In contrast, when X = BAr F 4 we observe no evidence of contact ion pairs, and the change in dipole moment upon photoexcitation is positive, as expected. These results are consistent with an excited-state ion-pair reorganization mechanism that cancels the dipole moment of the lowest-lying MLCT state when X = PF - 6 . We suggest that this phenomenon may explain the recently observed dependence of photocatalytic activity on counter-ion identity in similar iridium(III)-based photocatalysts. Ion pair reorganisation can be expected to reduce the excited-state potential energy and the proposed migration of the counter anion to the most positively charged region of the complex may limit the ability of these catalysts to drive oxidative chemistry. Finally, unrelated to ion pair dynamics, the measured dipole moment of the relaxed MLCT dtbpy state in [Ir[dF(CF 3 )ppy] 2 (dtbpy)]X is much smaller than naive point-charge calculations suggest, which, combined with a small polarizability volume indicate a rather localized final state of mixed metal-ligand character, in contrast with the highly polarizable initial MLCT states observed on the timescale of our instrument response. Future work should explicitly test to what extent ion pair reorganisation, the excited-state dipole moment and polarizability volume of photoredox catalysts may influences their reactivity.