Co-ion (5 mol %) substitution in Na1/2Bi1/2TiO 3 (NBT) host lattice and their effects on the structural, ferroelectric and dielectric behavior has been investigated thoroughly in this present study. The substituted Co-ion at Ti-site acts an acceptor type doping and hardens (i.e., increase in coercivity) the system without any noticeable change in the remanent polarization values. However, the intermediate antiferroelectric (AFE) ordering which exists between 200 C-280 C in NBT system has been suppressed due to Co-ion substitution, which is an interesting feature for device applications. © 2014 Author(s).