Steve H Park, Jieun Jang, Kwangmin Shin, and Hyunwoo Kim  We disclose a general electrocatalytic hydroetherfication for modular synthesis of alkyl aryl ethers by utilizing a wide range of alkenes and phenols. The integration of the two involves an electrochemically instigated cobalt-hydride catalyzed radical–polar crossover of alkenes that enables the generation of key cationic intermediates, which could readily be entrapped by challenging nucleophilic phenols. We highlight the importance of precise control of the reaction potential by electrochemistry in conjunction with the decisive role of HFIP as the co-solvent to obtain optimal and exclusive chemoselectivity. Notably, this reaction system is pertinent to late-stage functionalization of pharmacophores that contain alkyl aryl ethers which has constantly been challenged since traditionally unconventional methods. https://doi.org/10.1021/acscatal.2c02436