A one-piece structural fuse assembly is disclosed that is formed from a single piece of structural steel such as a beam. In embodiments, a first flange of the beam may form the fuse base, and a portion of the web of the beam may form the fuse plate. Additionally, a buckling restraint plate of the structural fuse assembly may be formed from a second flange of the beam, and the spacers of the structural fuse assembly may be formed from a portion of the web unused by the fuse plate. In examples, all of the components cut from the single piece of the beam are used in a single structural fuse assembly.