Herein, we describe the development of a copper-catalyzed C(sp3) amination of unactivated secondary alkyl iodides mediated by diaryliodonium salts. Our protocol is enabled by the intermediacy of aryl radical species that undergo halogen atom transfer prior to interfacing with copper catalysts, thus setting the basis for a C-N bond formation at sp3-hybridized carbons. The method is characterized by its mild reaction conditions, excellent regioselectivity, and wide substrate scope.