In this paper, the problem of nonlinear Sliding Mode (SM) output regulation is addressed. In particular, a state feedback SM regulator problem is formulated, taking the concepts related to the zero output tracking submanifold as a starting point, and a solution is proposed for general nonlinear affine control systems subject to unmodeled time-varying disturbance. Then, the problem is studied for the particular class of nonlinear systems presented in the so-called Regular form. The effectiveness of the proposed method is demonstrated by the application to the Pendubot system. (C) 2017 Elsevier Ltd. All rights reserved.