Research in indoor localization has received increasing focus recently due to the various applications location-based services can provide, such as use cases in emergency response, health care, targeted marketing, and assets tracking. Extending indoor localization to multi-floor environments with accurate floor or height estimation helps exploit localization services more fully. However, the literature lacks an up-to-date survey that thoroughly discusses indoor localization in the multi-floor setting. This survey provides an exhaustive review of these systems to provide insights for further research toward better localization systems. We give a detailed description of the different indoor localization technologies such as WiFi, cellular, and various sensors, used with techniques such as fingerprinting and Pedestrian Dead Reckoning (PDR), underlining their use in the 3D context of multi-story environments. Moreover, we review several existing systems, highlighting their approaches’ strengths and limitations. The survey’s primary focus is systems addressing the localization of users and their devices. We also overview different metrics used in evaluating the systems, such as localization accuracy, deployment cost, scalability, robustness, generalizability, ubiquity, and energy efficiency. Furthermore, we discuss various challenges in localization, highlighting those that arise with multi-floor scenarios and indicating directions for further research. No data was collected for this work.