High entropy alloys (HEA) are promising for applications involving extreme environmental exposure because of their excellent stability, which they maintain at high temperatures. This work studies the corrosion resistance of AlFeCrCoNi and FeCrMoAlTiNi in molten mineral salts and compares it with a reference stainless steel currently used in thermosolar plants. In addition to traditional casting, PM processing has been adopted in order to better understand how changes in the microstructure affect the behavior of alloys. To enable more control over the microstructural properties, the use of a fast sintering technology, Spark Plasma Sintering (SPS), is explored. Two combinations of molten salts have been used to monitor the corrosion behavior using polarization and electrochemical impedance spectroscopy (EIS). The traditional solar salt, a nitrate mixture, and a second salt mixture made of chlorides were proposed because of their higher heat capacity and lower price. The results indicate a promising use of HEA in applications in extreme and corrosive environments.