The construction of C−N bonds by free radical reactions represents a powerful synthetic approach for direct C−H amidations of arenes or heteroarenes. Developing efficient and more environmentally friendly synthetic methods for C−H amidation reactions remains highly desirable. Herein, metal‐free electrochemical oxidative dehydrogenative C−H amidations of heteroarenes with N‐alkylsulfonamides have been accomplished. The catalyst‐ and chemical‐oxidant‐free C−H amidation features an ample scope and employs electricity as the green and sole oxidant. A variety of heteroarenes, including indoles, pyrroles, benzofuran and benzothiophene, thereby underwent this C(sp2)−H nitrogenation. Cyclic voltammetry studies and control experiments provided evidence for nitrogen‐centered radicals being directly generated under metal‐free electrocatalysis.