  The light-cone distribution amplitudes (LCDAs) serve as important
non-perturbative inputs for the study of hard exclusive processes. In this
paper, we calculate ten LCDAs at twist-2 for the S-wave and P-wave $B_c$ mesons
up to the next-to-leading order (NLO) of the strong coupling $\alpha_s$ and
leading order of the velocity expansion. Each one of these ten LCDAs is
expressed as a product of a perturbatively calculable distribution and a
universal NRQCD matrix-element. By use of the spin symmetry, only two NRQCD
matrix-elements will be involved. The reduction of the number of
non-perturbative inputs will improve the predictive power of collinear
factorization.
