Metal-based additive manufacturing (AM) is a topic that cannot escape attention in most engineering fields. Its capabilities of having complex parts manufactured on demand, while reducing waste and cost, has raised the attention of the aerospace, automotive, and biomedical industries. Nevertheless, additively manufactured parts need to be proven to meet or exceed the quality and performance characteristics of their conventionally manufactured counterparts. Nondestructive evaluation (NDE) plays a critical role in the acceptance of AM, and reference specimens should be available for the performance evaluation of applicable techniques. From an NDE perspective, AM poses unique challenges, such as geometrically complex parts and manufacture-introduced flaws; anisotropy of mechanical, electrical, and elastic properties; as well as rough surface finish. Part quality and performance have to be assessed through a series of tests, including nondestructive ones. The detection capability of an NDE technique has to allow finding discontinuities smaller than the maximum allowable size. Development of NDE procedures along with design of suitable reference blocks need to be prioritized before the adoption of AM for mass production. Considering the lack of reference blocks for AM, with discontinuities specific to these manufacturing technologies and known critical defect type and size, some insights could be gained from the existing knowledge of inspecting conventionally manufactured parts. In this study, common eddy current reference blocks of aluminum and titanium alloys are examined by comparison with respect to fabrication modes (i.e., conventional versus additive). Maintaining the same instrumentation, parameters, procedures, and interpretation schemes, the eddy current technique is used to evaluate potential changes in inspection indications between the two manufacturing technologies. Moreover, metallography is performed on all blocks in an attempt to link microstructure with eddy current responses.