In this paper, a comprehensive assessment of design parameters for various beam theories subjected to a moving mass is investigated under different boundary conditions. The design parameters are adopted as the maximum dynamic deflection and bending moment of the beam. To this end, discrete equations of motion for classical Euler–Bernoulli, Timoshenko and higher-order beams under a moving mass are derived based on Hamilton's principle. The reproducing kernel particle method (RKPM) and extended Newmark-β method are utilized for spatial and time discretization of the problem, correspondingly. The design parameter spectra in terms of the beam slenderness, mass weight and velocity of the moving mass are introduced for the mentioned beam theories as well as various boundary conditions. The results indicate the existence of a critical beam slenderness mostly as a function of beam boundary condition, in which, for slenderness lower than this so-called critical one, the application of Euler–Bernoulli or even Timoshenko beam theories would underestimate the real dynamic response of the system. Moreover, there would be a roughly linear relation between the weight of the moving mass and the design parameters for a certain value of the moving mass velocity in most cases of boundary conditions.