Barnwell is a city located in South Carolina. With a 2020 population of 4,223, it is the 74th largest city in South Carolina and the 5245th largest city in the United States. Barnwell is currently declining at a rate of -1.68% annually and its population has decreased by -11.09% since the most recent census, which recorded a population of 4,750 in 2010. Barnwell reached it's highest population of 5,572 in 1980. Spanning over 8 miles, Barnwell has a population density of 538 people per square mile.
The average household income in Barnwell is $39,077 with a poverty rate of 35.55%. The median rental costs in recent years comes to $652 per month, and the median house value is $104,100. The median age in Barnwell is 39.1 years, 37 years for males, and 39.7 years for females. For every 100 females there are 71.9 males.