The properties of metallic materials produced through additive manufacturing (AM), including their corrosion behavior, depend on various parameters such as the type of AM technique, processing parameters, built environment, and the feedstock used [1]. These factors collectively influence the occurrence of processing defects and the microstructure of the alloy, which can be controlled through feedstock modifications. To illustrate the impact of feedstock modification on both microstructure and corrosion, two examples will be presented. These examples will compare the corrosion behavior of additively manufactured 316L stainless steel (SS) produced using three different types of feedstocks: the as-received feedstock, feedstock modified with CrN, and feedstock modified with carbon nanotubes. The feedstock modification was carried out by ball milling of commercial 316L SS powder with the selected additive [2-4]. Test coupons were produced by laser powder bed fusion of the commercial feedstock and modified feedstock. Corrosion resistance was evaluated using cyclic potentiodynamic polarization tests in NaCl solution. The pitting and repassivation potentials of the 316L SS produced by modified feedstock were significantly higher compared to those of 316L SS produced using as-received feedstock [2-4]. The mechanistic aspects of the feedstock modifications and their influence on corrosion behavior will be discussed in detail.