Brandon, SD has a population of 9,674 and is the 4,035th largest city in the United States. The population density is 1,798 per sq mi which is 16533% higher than the South Dakota average and 1885% higher than the national average. The median age in Brandon is 34 which is approximately 7% lower than the South Dakota average of 37. In Brandon, 66% of the population over 15 years of age are married, 97% speak English and 1% speak Spanish. 59% of Brandon residents were born in South Dakota, 40% were born out of state, 0% were born outside of the United States and 1% were foreign born.