Electro- and photochemical CO₂ reduction (CO₂R) is the quintessence of modern-day sustainable research. We report our studies on the electro- and photoinduced interfacial charge transfer occurring in a nanocrystalline mesoporous TiO₂ film and two TiO₂/iron porphyrin hybrid films (meso-aryl- and β-pyrrole-substituted porphyrins, respectively) under CO₂R conditions. We used transient absorption spectroscopy (TAS) to demonstrate that, under 355 nm laser excitation and an applied voltage bias (0 to −0.8 V vs Ag/AgCl), the TiO₂ film exhibited a diminution in the transient absorption (at −0.5 V by 35%), as well as a reduction of the lifetime of the photogenerated electrons (at −0.5 V by 50%) when the experiments were conducted under a CO₂ atmosphere changing from inert N₂. The TiO₂/iron porphyrin films showed faster charge recombination kinetics, featuring 100-fold faster transient signal decays than that of the TiO₂ film. The electro-, photo-, and photoelectrochemical CO₂R performance of the TiO₂ and TiO₂/iron porphyrin films are evaluated within the bias range of −0.5 to −1.8 V vs Ag/AgCl. The bare TiO₂ film produced CO and CH₄ as well as H₂, depending on the applied voltage bias. In contrast, the TiO₂/iron porphyrin films showed the exclusive formation of CO (100% selectivity) under identical conditions. During the CO₂R, a gain in the overpotential values is obtained under light irradiation conditions. This finding was indicative of a direct transfer of the photogenerated electrons from the film to absorbed CO₂ molecules and an observed decrease in the decay of the TAS signals. In the TiO₂/iron porphyrin films, we identified the interfacial charge recombination processes between the oxidized iron porphyrin and the electrons of the TiO₂ conduction band. These competitive processes are considered to be responsible for the diminution of direct charge transfer between the film and the adsorbed CO₂ molecules, explaining the moderate performances of the hybrid films for the CO₂R.