Swansea, SC has a population of 893 and is the 15,851st largest city in the United States. The population density is 428 per sq mi which is 190% higher than the South Carolina average and 373% higher than the national average. The median age in Swansea is 42 which is approximately 9% higher than the South Carolina average of 39. In Swansea, 50% of the population over 15 years of age are married, 98% speak English and 2% speak Spanish. 85% of Swansea residents were born in South Carolina, 15% were born out of state, 0% were born outside of the United States and 0% were foreign born.