Photoredox catalysis has been developed to achieve oxidative C–H chlorination of aromatic compounds using NaCl as the chlorine source and Na₂S₂O₈ as the oxidant. The reactions occur at room temperature and exhibit exclusive selectivity for C(sp²)–H bonds over C(sp³)–H bonds. The method has been used for the chlorination of a diverse set of substrates, including the expedited synthesis of key intermediates to bioactive compounds and a drug.