PLUTO, TEXAS. Pluto is near the Hill county line fifteen miles southwest of Waxahachie in western Ellis County. A post office was established there in 1894 and operated until 1905. In 1989 mail was received from Milford. The population was 200 in 1896, when three doctors practiced medicine in Pluto. The town had a store, a gin, a gristmill, and Methodist and Presbyterian churches. The population of Pluto remained stable at thirty-four from 1933 to 1944. The name was still listed as a community in 1990. In 2000 the population was fifteen.