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The electrocaloric effect (ECE) has attracted significant interest in the development of environmentally friendly solid-state refrigerators. To maximize the magnitude of the ECE at ambient temperature, several approaches have been applied, including the optimization of composition, microstructure, and field-protocol. In this paper we show that defect-related aging can effectively tune the ECE in lead-free 0.95(Na0.5Bi0.5)TiO3-0.05BaTiO3 ceramics at room temperature. The ECE is measured both directly and indirectly at different stages of aging. It reaches a maximum near the transition temperature between the relaxor and field-induced ferroelectric states. This temperature was shown to decrease upon aging, leading to a gradual shift in the ECE maximum toward room temperature. We have attributed the aging phenomena in the material under study primarily to the formation of dipolar defects consisting of vacancies in the A- and oxygen sublattices, and their alignment within the ferroelectric domains.