Reported herein is a visible light-induced C-H trifluoromethylation of quinoxalin-2(1H)-ones with CF3SO2Cl as CF3 radical source under photocatalyst-free conditions. The reaction proceeds smoothly through a radical process in the absence of photocatalyst and oxidant in moderate to good yields, thus offering an efficient and green method for the synthesis of 3-trifluoromethyl quinoxalin-2(1H)-ones.(C) 2022 Elsevier Ltd. All rights reserved.