A visible‐light‐inducedmetal‐free catalytic system was developed for the synthesis of arylphosphonates starting from arylhydrazines and trialkylphosphites. By using the inexpensive eosin B as catalyst, sub‐stoichiometric amounts of DABCO, and ambient air as oxidant, diverse arylphosphonates were obtained under visible‐light irradiation. Notably, this catalytic system is suitable for gram‐scale reaction