<p>The paper deals with three different theoretical models aimed at the calculation of the strain energy stored in multi-twinned icosahedral small particles of materials with the face-centered cubic crystalline structure. These models are the distributed disclination model, the revisited discrete disclination model, and the finite element model. They are utilized to find elastic strains, stresses and strain energy in icosahedral small particles under the assumptions of their spherical shape and linear and isotropic elasticity of their materials. Within the discrete disclination model, the pair interaction energy of intersecting wedge disclinations in an elastic sphere is derived in an explicit analytical form. The provided analysis of elastic fields and energy determines the accuracy of the employed assumptions. It is shown that the simplifying assumption of radially homogeneous distribution of disclination distortion, employed in the distributed disclination model, leads to insignificant errors (less than 4%) in the strain energy calculation as compared with the advanced (but more complicated) discrete disclination model. Moreover, it is demonstrated that the accuracy of finite element modeling noticeably depends on the elastic properties of particle material. In fact, the discrepancy between the results of the finite element modeling and the analytical calculations increases with the Poisson ratio of the particle material; however, it does not exceed ~ 14%&#xa0;even in the limiting case when the Poisson ratio takes the maximum value 0.5. Thus, the results of both finite element and analytical models are in a good agreement. This output allows to employ both the approaches in future analysis of physical properties and mechanical stability of icosahedral small particles.</p> Graphical abstract <p></p>