A process for preparing poly(trimethylene terephthalate) fibers including (a) providing a poly(trimethylene terephthalate) composition comprising about 0.05 to about 10 weight % ionomer and (b) spinning the polymer composition to form fibers. In addition, a poly(trimethylene terephthalate) fiber including poly(trimethylene terephthalate) with about 0.1 to about 10 weight % ionomer dispersed throughout the poly(trimethylene terephthalate), and use thereof in yarns, fabrics, and carpets, as well as the yarns, fibers and fabrics.