The deployment of small satellites has been rapidly increasing due to their numerous advantages, including significantly lower launch costs, improved space debris mitigation and a reduced environmental footprint. Despite these benefits, small satellites face a critical engineering problem: their limited surface area and compact architectures lead to high heat fluxes that current thermal control solutions struggle to dissipate effectively. In this context, the development of advanced thermal control systems (TCS) is essential to maintain satellite components within their operational temperature limits by balancing internal and external heat loads. Two-phase flow-based thermal control systems, including heat pipes, phase change materials, and mechanically pumped loops, have been successfully used in larger spacecraft but remain largely unexplored for small satellites. These technologies represent a promising approach to managing the rising thermal loads expected in next-generation small satellite systems. This gap highlights the lack of comprehensive assessment regarding their scalability, microgravity behavior, and suitability for emerging high-power small-satellite platforms. The novelty of this review lies in summarizing recent advancements in two-phase thermal control systems while identifying the current limitations and open challenges that must be addressed to ensure their reliable operation. By clarifying these limitations and mapping current research efforts, the study provides critical insights needed to guide future system development. The review underlines how future progress in this field will strongly depend on advances in system miniaturization, including novel materials and manufacturing techniques, as well as deeper understanding of two-phase transport phenomena in microgravity, and rigorous experimental validation under relevant space conditions. Overall, this study highlights the growing potential of two-phase systems to address escalating thermal loads in next-generation small satellites and outlines the key directions required to achieve their reliable and widespread adoption. ... Read more