  In this paper, we calculate the next-to-leading order (NLO) quantum
chromodynamics (QCD) corrections to the exclusive processes $B_c^+\to
\chi_{cJ}(h_c)\pi^+$ in the framework of the nonrelativistic QCD (NRQCD)
factorization formalism. The results show that NLO QCD corrections markedly
enhance the branching ratios with $K$ factors of about 2.5. In combination with
the study of $B_c^+\to J/\psi\pi^+$, we find that the NLO NRQCD prediction for
the ratio of branching fractions $\frac{\mathcal{B}(B_c^+\to
\chi_{c0}\pi^+)}{\mathcal{B}(B_c^+\to J/\psi \pi^+)}$ is then compatible with
the experimental measurement.
