Four polyols intended for application in polyurethanes were synthesized by oxirane ring opening in epoxidized soybean oil with hydrochloric acid, hydrobromic acid, methanol, and hydrogen. The structures of the polyols were characterized by spectroscopic, chemical, and physical methods. The brominated polyol had 4.1 hydroxy groups, whereas the other three polyols had slightly lower functionality. The densities, viscosities, viscous-flow activation energies, and molecular weights of the polyols decreased in the following order: brominated > chlorinated > methoxylated > hydrogenated. All the polyols were crystalline solids below their melting temperature, displaying multiple melting peaks. The methoxylated polyol was liquid at room temperature, whereas the other three were waxes.