Southside Place incorporated in June 1931 with 600 residents. The city council first met on June 15 of that year. On August 3, 1934 the city council passed a resolution that declared Southside Place an incorporated city. Because of the incorporation, Houston did not incorporate Southside Place's territory into its city limits, while Houston annexed surrounding areas that were unincorporated. A post office opened in 1940. Before World War II the population stabilized around 1,400. In the 1960s the city reached a high 1,500 residents. By 1979 the number of residents fell to 1,263. In 1988 the city had 1,560 residents. In 1990 the city had 1,384 residents.