Smithville is a city in Bastrop County, Texas, United States, near the Colorado River. The population was 3,817 at the 2010 census.
Smithville was established in 1827, when Thomas Gazely settled in the area and operated a store. A community sprang up around the store, and it was named Smithville, in honor of another early resident, William Smith. Gazely's store closed upon his death in 1853. J.P. Jones and Frank Smith opened another store in the community in 1867. A Presbyterian Church was organized in 1871. A post office was opened in 1876. In 1887, the railroad came to Smithville, causing the town's population to boom, and the town was incorporated in March 1895. By 1900, Smithville had a population of 2,577.