We　report　here　an　electrophotoredox　cerium-catalyzed　ligand-to-metal-charge-transfer　(LMCT)　strategy　to　incorporate　a　broad　range　of　primary,　secondary　and　tertiary　carboxylic　acids　into　radical　cyclization　cascades　under　external　oxidant-free　conditions.　This　protocol　provides　a　solution　to　address　the　challenges　associated　with　alkylated　benzimidazo-fused　isoquinolinones　synthesis.　The　high　functional　group　compatibility　was　demonstrated　by　the　tolerance　of　ester,　carbonyl,　amide,　sulfonyl　and　hydroxyl　groups.　We　report　an　electrophotoredox　cerium-catalyzed　LMCT　strategy　to　incorporate　carboxylic　acids　into　radical　cyclization　cascades.　This　protocol　provides　a　solution　to　address　the　challenges　in　alkylated　benzimidazo-fused　isoquinolinone　synthesis.