Herein, we disclose a straightforward approach to access transition-metal-free reductive N-formylation of nitroarenes. This reaction integrates the dual role of rongalite, which acts as a reductant and a C1 building block concurrently. This provides an alternative method for the synthesis of N-aryl formamides from nitroarenes, including the construction of a C-N bond. The utility of this protocol was demonstrated by scale-up synthesis and late-stage functionalizations of complex molecules.