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Abstract We reconsider QCD factorization for the leading power contribution to the γ * γ → π 0 form factor F γ*γ→π 0(Q 2) at one loop using the evanescent operator approach, and demonstrate the equivalence of the resulting factorization formulae derived with distinct prescriptions of γ 5 in dimensional regularization. Applying the light-cone QCD sum rules (LCSRs) with photon distribution amplitudes (DAs) we further compute the subleading power contribution to the pion-photon form factor induced by the “hadronic” component of the real photon at the next-to-leading-order in Oαs $$ \mathcal{O}\left({\alpha}_s\right) $$, with both naive dimensional regularization and ’t Hooft-Veltman schemes of γ 5. Confronting our theoretical predictions of F γ*γ→π0 (Q 2) with the experimental measurements from the BaBar and the Belle Collaborations implies that a reasonable agreement can be achieved without introducing an “exotic” end-point behaviour for the twist-2 pion DA.