Saudi Arabia’s transition toward a carbon-neutral energy system requires a reliable and economically optimized hydrogen transport infrastructure. This study develops a mixed-integer linear programming (MILP) model to design a cost-effective, all-domestic green hydrogen network connecting eight major cities across the Kingdom. The model integrates multiple transportation modes including pipelines, compressed gas trailers, and liquid hydrogen tankers to evaluate logistics costs between renewable production sites, industrial demand centers, and storage facilities. By minimizing the total system cost, which encompasses production, storage, and transportation, the model identifies optimal facility locations and capacity configurations under uncertain demand scenarios. Results indicate that production costs dominate total expenditures (70–75%), while transportation and storage contribute approximately 15–20% and 5–10%, respectively. Dammam, Medina, and Tabuk emerge as the most cost-efficient production hubs, balancing renewable resource availability and industrial proximity. Gaseous hydrogen proves most viable for short-distance distribution, while liquid hydrogen and ammonia are optimal for longer or export-oriented routes. The optimized configuration yields minimum annual system cost demonstrating that integrated, data-driven planning can significantly reduce hydrogen supply chain expenses. This research offers a quantitative framework to support national policymakers and investors in advancing Saudi Arabia’s hydrogen economy and achieving Vision 2030 goals of sustainability and energy diversification.