The population of Sweeny, Texas is approximately 3,739 people. The median age is 40, and 51% of Sweeny's residents are male. There are 28% single male families, 32% single female families, and 46% of households have two or more people. The median household income in Sweeny is $62,763, and the average family income is $33,804. More than 87% of residents have completed high school, while 10% have an associate's or bachelor's degree, and 2% have completed graduate school.