Thin-film semiconductors are excellent candidates for converting solar energy into chemical energy through water splitting because of their outstanding physical and chemical properties. This review aims to provide the most recent findings on the production of energetic vectors from photo(electro)catalytic water splitting using thin-film semiconductors as catalysts. Recent successful cases are discussed to provide the scientific community with a guide for the design of new and advanced thin-film semiconductors with maximum efficiency to scale the process. In addition, an analysis of the use of coatings to provide a higher amount of catalyst for photo(electro)catalytic H2 production is discussed. Some of the most critical challenges in this reaction have been effectively addressed by applying thin films, such as charge recombination, light absorption, catalyst recovery, and stability. In addition, the design of adequate thin-film photo(electro)chemical reactors is a critical step in improving efficiency and avoiding the mass transfer limit steps. However, further research is needed to provide continuous and low-cost manufacturing deposition techniques that favor optimal conditions to produce clean and renewable H2.