Cellulosic fibers having enhanced reversible thermal properties and applications of such cellulosic fibers are described. In one embodiment, a cellulosic fiber includes a fiber body including a cellulosic material and a set of microcapsules dispersed in the cellulosic material. The set of microcapsules contain a phase change material having a latent heat of at least 40 J/g and a transition temperature in the range of 0.degree. C. to 100.degree. C., and the phase change material provides thermal regulation based on at least one of absorption and release of the latent heat at the transition temperature. The cellulosic fiber can be formed via a solution spinning process, and can be used in various products where thermal regulating properties are desired.