Smithville is a town located in the U.S. state of Arkansas. It is within and lies at the crossroads of Western Lawrence County. It has a total area of 0.60 square miles at 36°4′48″N 91°18′14″W. The elevation is 121 feet above sea level. As of the 2010 census data, it had a total population of 78. The population density was 119.60/sq mi. Estimated per capita income in 2016 was $20,868. It has Zip code 71658. It has Zip code 72466.