Hydrogen is envisioned to become a fundamental energy vector for the decarbonization of energy systems. Two key factors that will define the success of hydrogen are its sustainability and competitiveness with alternative solutions. One of the many challenges for the proliferation of hydrogen is the creation of a sustainable supply chain. In this study, a methodology aimed at assessing the economic feasibility of holistic hydrogen supply chains is developed. Based on the designed methodology, a tool which calculates the levelized cost of hydrogen for the different stages of its supply chain: production, transmission & distribution, storage and conversion is proposed. Each stage is evaluated individually, combining relevant technical and economic notions such as learning curves and scaling factors. Subsequently, the findings from each stage are combined to assess the entire supply chain as a whole. The tool is then applied to evaluate case studies of various supply chains, including large-scale remote and small-scale distributed green hydrogen supply chains, as well as conventional steam methane reforming coupled with carbon capture and storage technologies. The results show that both green hydrogen supply chains and conventional methods can achieve a competitive LCOH of around €4/kg in 2030. However, the key contribution of this study is the development of the tool, which provides a foundation for a comprehensive evaluation of hydrogen supply chains that can be continuously improved through the inputs of additional users and further research on one or more of the interconnected stages.