Ammonia has emerged as a leading hydrogen carrier for long-distance energy transport, particularly for Europe, which is expected to be one of the largest importers of ammonia by 2050. Ammonia’s energy vector and decarbonizing potential rely on its relative to hydrogen mature infrastructure that might accelerate the realization of the proposed hydrogen supply chain to Europe. Countries such as the Netherlands, Belgium, France, and Germany have ports capable of serving as an ammonia gateway to Europe. This study presents a techno-economic assessment of ammonia-based hydrogen supply chains, focusing on maritime transport and hydrogen recovery via cracking at the import terminal. The analysis evaluates different ammonia production pathways, which are commonly classified by color: gray, blue, and green. The supply chains of ammonia to Europe were used as a blueprint for mapping out the supply chain model for this study, from production country, port, ammonia and hydrogen synthesis, storage, maritime shipping routes, and on-site import terminal cracking. Considering that the majority of ammonia imports to Europe are sea-borne imports, the integration of a multi-criteria decision analysis framework to support the techno-economic assessment and hence decision-making is essential. The multi-criteria decision analysis integrates economic, environmental, and technical indicators to enable the comparative assessment of different colors from the same export country. The results show that, even though green ammonia pathways offer long-term sustainability advantages, cost competitiveness remains sensitive to export countries’ infrastructure development, water supply, and political stability, in addition to the import countries, i.e., Europe’s “low-emission fuel” regulatory framework. Finally, the study explores the potential of defining and integrating the “concept” of energy efficiency and exergy efficiency with respect to the building block of a supply chain, as supplementary evaluation parameters. Parameters that might hold an assessment potential within a decision-making framework.