Abstract <p>NiTi-based shape memory alloys, owing to their unique pseudoelastic and shape memory effects, are widely used in miniaturized devices such as micro-actuators, MEMS, cardiovascular-stents etc. For successful utilization, evaluating small-scale mechanical performance is crucial, which however is highly dependent on the microstructure and phase contents. The present study investigates the role of microstructure and experimental conditions on localized mechanical characteristics through systematic indentation tests. Ni-rich NiTi alloy is initially solutionized and compared with its aged counterpart. High-resolution transmission electron microscopy reveals the presence of equiaxed austenite B2 phase in the solutionized alloy whereas a mixture of austenite, R-phase and Ni₄Ti₃ precipitates in the aged alloy. These microstructural evolution results to increased hardness for the aged NiTi alloy, although showing prominent indentation size effect. Nevertheless, considering pseudoelasticity is crucial for the design of NiTi components, the indentation depth recoverability of the studied alloys is systematically analyzed using a Berkovich and a sphero-conical indenter, revealing deviations in recoverability response. Interestingly, precipitation-strengthened NiTi alloy shows a higher recoverability ratio (%) using sphero-conical indenter. Nanomechanical response of the solutionized and aged NiTi alloys to varying indentation loading rates is scrutinized further, revealing notable influence particularly on the aged NiTi alloys. Overall, the study highlights the importance of subjecting NiTi to optimized thermal treatment condition, thereby modifying the microstructure, for attaining the required performance for targeted application.</p> Graphical Abstract <p></p>