Additive manufacturing (AM) is emerging as an important new technology that provides the ability to produce unique components and subassemblies that cannot be produced by conventional manufacturing methods. While the microstructure of AM metals is distinct from typical casting and wrought product, in some cases, the microstructures of AM metals can have features similar to welded microstructures. For component design in high-value applications, such as in aggressive environments, the effect of these unique microstructures on mechanical performance must be evaluated. This report explores hydrogen-assisted fracture of austenitic stainless steels produced by additive manufacturing. In particular, thermal hydrogen precharging is used as a surrogate for testing in high-pressure gaseous hydrogen of additively-manufactured 304L austenitic stainless steel. The fracture properties of the hydrogen-precharged additively-manufactured 304L austenitic stainless steel are reported and compared to performance of hydrogen-precharged wrought 304L and welded 304L stainless steels. The measured performance of conventional and AM material is discussed in the context of their respective microstructures with emphasis on the prognosis of AM austenitic stainless steels for service in gaseous hydrogen environments.