I haven't started adding colorants to my soaps yet, so I don't know if colors will fade. They stay in a very well lit room, with east, south, and west facing windows, and the two broad spectrum grow lights. I haven't noticed fading in my natural soap (milk, shea, oatmeal) or my pink himalayan salt bar. The next soap I do, I want to color it with paprika or turmeric, and I will certainly take note of any color changes.Hey Jessica, I've been considering putting some of mine on a bakers' rack in a small, sunny, well-ventilated bathroom, but worried about fading. Have you noticed any of that?