0.36BiScO(3)-0.64PbTiO(3) (BS-PT) ceramics are promising materials for high temperature piezoelectric applications. However, the varied performance parameters reported indicate that careful study of the fabrication technique and its influence on the electrical behavior of the resultant BS PT are necessary. In this paper, two samples of the BS PT, one with a 1.0 wt% excess of both the starting raw materials Bi2O3 and PbO (BS-PT-I) and the other with a 1.0 wt% excess of PbO (BS PT-II) were synthesized to address their influence on the sintering behavior, phase evolution and electrical behaviors of the resultant ceramics. It was found that the cell volume of the dominant tetragonal phase of the BS PT increases slightly with the increase of the sintering temperature. Excess of Bi2O3 and PbO, resulted in phase separation in the resultant BS PT ceramics. The very large dielectric tunability obtained indicates that the BS PT has significant potential to be used as tunable capacitors in the elevated temperature range. (C) 2015 Elsevier Ltd. All rights reserved.