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Abstract This study presents a Ni‐photoredox method for indoleN‐arylation, broadening the range of substrates to include indoles with unprotected C3‐positions and base‐sensitive groups. Through detailed mechanistic inquiries, a Ni(I/III) mechanism was uncovered, distinct from those commonly proposed for Ni‐catalyzed amine, thiol, and alcohol arylation, as well as from the Ni(0/II/III) cycle identified for amide arylation under almost identical conditions. The key finding is the formation of a Ni(I) intermediate bearing the indole nucleophile as a ligand prior to oxidative addition, which is rare for Ni‐photoredox carbon‐heteroatom coupling and has a profound impact on the reaction kinetics and scope. The pre‐coordination of indole renders a more electron‐rich Ni(I) intermediate, which broadens the scope by enabling fast reactivity even with challenging electron‐rich aryl bromide substrates. Thus, this work highlights the often‐overlooked influence of X‐type ligands on Ni oxidative addition rates and illustrates yet another mechanistic divergence in Ni‐photoredox C‐heteroatom couplings.