CePtSn belongs to the group of orthorhombic CeTX compounds. Similar to some other CeTX companions, it exhibits a pronounced anisotropy of electronic and elastic properties with respect to the direction of an applied magnetic field. We report on our study of the temperature and magnetic field evolution of the thermal expansion and magnetostriction, acquiring all the major components of the corresponding tensors. Also, the evolution of the electrical resistivity across the H‐T‐p space was investigated in order to confirm and extend the information on physics of the studied material. We have observed a significant dependence of elastic properties on the magnetic history for the magnetic field applied along the b-axis, which is reflecting a nontrivial evolution of magnetic ordering. Consequently, these results are discussed within the framework of the appearance of magnetism in the Ce(Pt,Ni)Sn system and the relationship between the elastic properties and the results of the investigation of pressure induced effects.