[en] We investigate the impact of statistical uncertainties in the two-nucleon potentials on the neutron–deuteron elastic scattering and the deuteron breakup reaction observables at incoming nucleon kinetic energy up to 200 MeV. To that end we use the semi-phenomenological one-pion-exchange- Gaussian two-nucleon potential developed by the Granada group and the recent semi-local momentum-space regularized chiral nucleon–nucleon interaction at various orders, neglecting the three-nucleon force present in the three-nucleon system. The magnitudes of statistical uncertainties for these two potentials are found to be rather similar. For the chiral potential, we also show truncation errors estimated, among others, using the Bayesian method and discuss the residual cutoff dependence. The statistical uncertainty is generally found to be smaller than the truncation errors except for certain observables calculated at high chiral orders at nucleon energies up to 65 MeV. In general, magnitudes of the theoretical uncertainties are small and amount up to 0.5%–4%, depending on the observable and energy. (paper)