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Classical trajectory simulations, using potential energy surfaces of ab initio quality, are performed to investigate the influence of crystal symmetry on the Eley–Rideal abstraction dynamics of N atoms colliding, under normal incidence, N-preadsorbed tungsten (100) and (110) surfaces. Low-energy reactivity (<0.5 eV collision energy) results much higher for the (110) crystallographic plane. Such a feature stems from the topology of the interactions upon approach of the N-gas atom toward the N adsorbate: the strong lateral corrugation responsible for a significant threshold for recombination on the (100) surface is much smoother on the (110) plane, allowing low-energy incident atoms to react. Temperature is found to only slightly affect reactivity.