Darlington County is also home to Coker College in Hartsville.

Darlington County is included in the Florence, SC Metropolitan Statistical Area.

While no records exist regarding the namesake of the county, it could possibly be named after Darlington, England.

The county seat is Darlington and the largest community is Hartsville.

At the 2010 census, there were 68,681 people, 26,531 households, and 18,552 families living in the county.

[14] At the 2000 census,[15] there were 67,394 people, 25,793 households, and 18,441 families living in the county.

25.10% of all households were made up of individuals, and 9.20% had someone living alone who was 65 years of age or older.

According to the 2000 census, Darlington County was classified as 41% urban and 59% rural.

The county's population is included within the Florence, SC Metropolitan Statistical Area.

[19] As of April 2024[update], some of the largest employers in the county include Coker University, Duke Energy Progress Inc, Sonoco, and Walmart.