The design of lead-free ceramics for piezoelectric energy harvesting applications has become a hot topic. Among these materials, Ba0.85Ca0.15Zr0.10Ti0.90O3 (BCZT) and BaTi0.89Sn0.11O3 (BTSn) are considered as potential candidates due to their enhanced piezoelectric properties. Here, the structural, electrical, piezoelectric and piezoelectric energy harvesting properties of the (1 − x)Ba0.85Ca0.15Zr0.10Ti0.90O3−xBaTi0.89Sn0.11O3 (xBTSn, x = 0.2, 0.4 and 0.6) system are investigated. A systematic study of the structural properties of the xBTSn samples was carried out using X-ray diffraction, Raman spectroscopy, and dielectric measurements. The addition of BTSn allows a successive phase transition, which broadens the application temperature range. The enhanced piezoelectric energy harvesting properties were found in the 0.2BTSn ceramic, where the large-signal and small-signal piezoelectric coefficients, piezoelectric voltage and the piezoelectric figure of merit reached 245 pm V−1, 228 pC N−1, 16.2 mV m N−1 and 3.7 pm2 N−1, respectively. Consequently, the combination of BCZT and BTSn could provide suitable lead-free materials with enhanced piezoelectric energy harvesting performances.