Empirical rule calculation, commonly used for phase selection of high entropy alloys (HEAs), provides valuable guidelines for designing multicomponent solid solutions. It is unknown whether the technique can offer a similar design strategy for multicomponent intermetallics that undergo B2−B19′ transformation. Establishing such guidelines can significantly accelerate the pace of discovery for new shape memory alloys (SMAs) by narrowing down the search area within the vast compositional design space of multicomponent alloys. In this study, we compiled hundreds of data on medium and high-entropy NiTi-based alloys exhibiting B2−B19′ transformation. Our objective was to construct a more comprehensive Ω−δ map and locate multicomponent SMAs on it. Additionally, we conducted a thorough analysis to establish a correlation between transformation temperatures and compositional features in medium and high-entropy SMAs (ME and HE-SMAs). This correlation can be leveraged to design SMAs with targeted transformation temperatures.