Stabilizer compositions for stabilizing materials against degradation due to thermal and ultraviolet light exposure are disclosed herein. In some instances, the stabilizer compositions include an ortho-hydroxyl tris-aryl-s-triazine compound; a hindered amine light stabilizer compound; a hindered hydroxybenzoate compound; a phosphite compound, an acid scavenger and/or thioester; and a hindered phenol antioxidant compound.