In this work, a comparative study between several numerical methodologies for the seismic analysis of offshore wind turbines on deep foundations (monobuckets or monopiles) is presented. Three formulations are compared within the scope of linear elasticity. First, a coupled Boundary Element -Finite Element (BEM-FEM) model is considered for obtaining the reference results. This methodology makes use of boundary elements to discretize the soil, while modelling the actual geometry of the hollow

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... through shell finite elements. The second model corresponds to a formulation based on the integral expression of the reciprocity theorem in elastodynamics and the use of specific Green's functions for the layered half space for the modeling of soil, and the treatment of the pile as unidimensional beam elements. Finally, a Beam-on-Dynamic-Winkler-Foundation (BDWF) model is also considered as a commonly used simple tool for the analysis of deep foundations. The results are presented in terms of variables of interest for the design of offshore wind turbines. From the analyses, the applicability range of these methodologies can be established depending on the properties of the turbine-foundationsoil system.