A Ru(II)-catalyzed C(sp2)-H trifluoromethylthiolation and thioarylation of indolines using bench-stable reagents have been explored. Diversely substituted indolines were functionalized at C7 position in good to excellent yields. Radical quenching, deuterium labeling, KIE, and reaction order determination experiments were performed to support the proposed reaction pathway. Gram-scale synthesis and post-transformation of the synthesized products have also been carried out to demonstrate the applicability of the developed catalytic protocol.