We present a single-crystal study of ThOs2Al10 and UOs2Al10, crystallizing in the YbFe2Al10-type orthorhombic structure. We have performed for the first time the refinement of their cage-type crystal structure and also first-principles calculations of their electronic structures. Moreover, we carried out the magnetic, thermal and transport measurements on a single-crystalline sample of UOs2Al10. Based on the local character of the 5f2−electron configuration of the U4+ ion in UOs2Al10, the effective crystal field (CF) potential in the intermediate coupling form was estimated using the CF level scheme, composed only of singlets. The obtained scheme satisfactorily reproduces both the magnetic susceptibility (measured along the three main crystallographic directions) and the Schottky-type anomaly of the specific heat. Both these data underline the ionic character of the central atom in its cage. The latter was estimated using the specific heat data of ThOs2Al10 as a phonon reference. In addition, the strong anisotropic behavior of the Seebeck coefficient measured along the two principal directions, namely a and b axes, and the low-temperature pronounced maximum along the latter axis have been approximately explained by the CF effect. As the calculations pointed out, the latter also dominates in the S-shaped temperature dependencies of the electrical resistivity, measured using the current flowing along the three main axes. Simultaneously, the magnetoresistivity reveals a strong metallic character of UOs2Al10 and an anisotropic electronic structure reflected in the anisotropic Fermi surface that certainly originate from a c-f hybridization effect in an orthorhombic unit cell. All these give rise to the typical metallic character in a similar way as it was previously found for Fe- and Ru-bearing analogs. Moreover, the coexistence of ionic and metallic characters of all these three cage-type compounds comes from the dual behavior of the U 5f electrons. In turn, the presence of low-frequency anharmonic Einstein modes reflects the regular rattling of the U4+ ion located in the [T4Al16] cage. This rattling is, however, less apparent for UOs2Al10 than for the Fe- and Ru-based counterparts, reported in our previous papers.