The highly corrosive behavior of ammonium chloride (NH4Cl) is known to originate from its intrinsic hygroscopic nature. Refining and co-processing process units for biofuels are often exposed to highly concentrated NH4Cl solution either resulting from water vaporization from an HCl and NH3 containing solution when the temperature increases or salt deposition from vapor phase when the temperature drops. For the latter case, once it reacts with water vapor present in the process, the deposited NH4Cl salts forms a concentrated and corrosive solution through deliquescence (unlike in conventional refinery). Consequently, severe pitting and localized corrosion are reported in hydrogenation and fluid cracking units. Therefore, studying corrosion resistance alloys (CRA) compatibility in the presence of concentrated NH4Cl salt solution is crucial to mitigate corrosion in the process. This paper reports the experimental evaluation of corrosion resistance of different CRAs, based on corrosion rate and stress corrosion cracking, exposed to saturated NH4Cl solution in the temperature range of 130-220°C.