Swansea is a city located in Illinois. With a 2020 population of 13,138, it is the 182nd largest city in Illinois and the 2547th largest city in the United States . Swansea is currently declining at a rate of -0.80% annually and its population has decreased by -2.17% since the most recent census, which recorded a population of 13,430 in 2010. Swansea reached it's highest population of 13,768 in 2012. Spanning over 7 miles, Swansea has a population density of 2,031 people per square mile.
The average household income in Swansea is $102,898 with a poverty rate of 7.60%. The median rental costs in recent years comes to $1,062 per month, and the median house value is $167,000. The median age in Swansea is 43.9 years, 42.2 years for males, and 45.6 years for females.