Near-zero strain hysteresis (H_s) is critical for the performance and reliability of electromechanical devices, yet its realization in environmentally friendly piezoelectric ceramics remains a challenge. Although defect engineering, phase boundary engineering, and the construction of polar nanoregions (PNRs) have been widely explored to reduce strain hysteresis, these individual approaches have yet to achieve significant improvements. Herein, we propose an effective strategy to engineer high-active glassy polar nanoregions (HAG-PNRs) and defect dipoles in Ba_(1−x)(Sn_0.11Ti_0.89)O₃–0.5xSb₂O₃ ceramics with multiphase coexistence. By reducing the domain switching energy barrier and frictional damping in piezoelectric ceramics, an ultralow strain hysteresis (~1.25%) is achieved, representing one of the lowest strain hysteresis values reported in ceramic systems to date. This work offers a novel design paradigm for developing BaTiO₃-based lead-free piezoceramics with near-zero strain hysteresis through the controlled formation of HAG-PNRs.

High-performance lead-free piezoelectric ceramics with knockdown strain hysteresis are key components of high-precision actuators. However, high strain hysteresis in BaTiO₃-based ceramics results in stability degradation, lifespan reduction, and inferior positioning accuracy. Therefore, in this work, a (1−x)Ba(Sn_0.11Ti_0.89)O₃–xSrTiO₃–0.6 wt% MnO₂ (BST–xST) composition is elaborately designed to reduce strain hysteresis. Ultralow strain hysteresis (4.8%) is achieved by adjusting the phase structure and domain configuration. The transmission electron microscopy (TEM) results revealed that the composition consists of a rhombohedral–orthorhombic–tetragonal–cubic (R–O–T–C) four-phase, nanodomains, and active polar nanoregions (PNRs). Moreover, the piezoresponse force microscopy (PFM) results revealed that these active PNRs can respond quickly to applied electric field stimuli. These findings provide a feasible path to prepare piezoelectric compositions with ultralow strain hysteresis.