Investigation of crystal structure and multiferroic properties of polycrystalline Bi1–xSmxFeO3 (0.1 ⩽ x ⩽ 0.2) samples was performed by X-ray diffraction, piezoresponse force microscopy and SQUID-magnetometry techniques. It was shown that increasing samarium content induced a polar-to-nonpolar phase transition near x = 0.2. Within the polar region, a rhombohedral and two orthorhombic modifications of Bi1–xSmxFeO3 were found. It was shown that samarium substitution resulted in the appearance of spontaneous magnetization, which was significantly enhanced upon the composition-driven transition from a rhombohedral to an orthorhombic phase.