A long-standing problem in paleoseismic studies is to distinguish between aseismic and seismic slips along faults. We address this problem by characterizing the magnetic fabrics of rock samples around mesoscale normal faults of aseismic origin, and comparing them to those around co-seismic normal faults. Detailed sampling profiles along traverses, <0.2 m up to ~20 m from both sides of the faults, indicate symmetric and unchangeable magnetic fabrics of deformation origin that are coaxial with the regional strain field. These results are essentially different from magnetic fabrics detected around co-seismic normal faults, which show fault-related fabrics with asymmetric and changeable orientations. The analysis demonstrates two end-member cases of magnetic fabrics in association with aseismic and seismic slips along faults. We suggest that magnetic fabric analysis provides a powerful and efficient tool to characterize inelastic deformation around faults, enabling to distinguish between seismic and aseismic slip histories.