FeCrAl alloys have become an extremely promising candidate material for accident tolerant fuel cladding because of their excellent resistance to high temperature steam oxidation and good corrosion behavior in light water reactor environment. While FeCrAl alloys have good mechanical properties when possessing a fine/ultrafine grained microstructure, they can suffer from embrittlement when possessing a coarse-grained microstructure. Thus, for commercial scale production, new fabrication techniques need to be investigated. Powder metallurgy and additive manufacturing methods have therefore become of interest for fabrication of FeCrAl alloy components due to the inherent grain refinement of the techniques. While powder metallurgy hot isostatic pressing (PM-HIP) microstructures are expected to perform well, the high number of fabrication defects (microcracks and porosity) in the additively manufactured (AM) alloy may increase surface area which could potentially increase the corrosion/oxidation rate for this material. In this study we have evaluated PM-HIP and AM C26M (Fe12Cr6Al2Mo) alloys in boiling water reactor and pressurized water reactor coolant conditions as well as in high temperature (1200 C) steam accident conditions in order to study the impact of the fabrication route on corrosion/oxidation behavior. Results showed no significant variation in mass change between the variants in hydrothermal corrosion and high-temperature steam exposure. During high-temperature steam oxidation C26M variants effectively formed 0.7-1.2 m thick stable protective alumina films. This study suggests FeCrAl alloys have excellent resilience to high temperature steam in nuclear reactor accident scenarios regardless of the fabrication method.