According to the U.S. Census Bureau, the county has a total area of 586.16 square miles (1,518.1 km), of which 580.66 square miles (1,503.9 km) is land and 5.50 square miles (14.2 km) (0.94%) is water.

• Sumter National Forest (part)

• Chester State Park
• Landsford Canal Forest Legacy Area
• Landsford Canal State Park
• Woods Ferry Recreation Area

• Broad River
• Catawba River
• Chester Reservoir
• Great Falls Lake
• Fishing Creek Lake

• York County – north
• Lancaster County – east
• Fairfield County – south
• Union County – west

• I-77
• US 21
• US 321
• 
  US 321 Bus.
• SC 9
• 
  SC 9 Bus.
• SC 49
• SC 72
• SC 97
• SC 99
• SC 121
• SC 215
• SC 223
• SC 901
• SC 909

As of the 2020 census, there were 32,294 people, 12,653 households, and 8,042 families residing in the county.

At the 2010 census, there were 33,140 people, 12,876 households, and 9,073 families living in the county. The population density was 57.1 inhabitants per square mile (22.0/km). There were 14,701 housing units at an average density of 25.3 units per square mile (9.8 units/km). The racial makeup of the county was 59.8% white, 37.4% black or African American, 0.4% American Indian, 0.3% Asian, 0.6% from other races, and 1.5% from two or more races. Those of Hispanic or Latino origin made up 1.4% of the population. In terms of ancestry, 19.9% were American, 7.5% were Irish, 5.6% were English, and 5.1% were German.

Of the 12,876 households, 34.1% had children under the age of 18 living with them, 44.5% were married couples living together, 19.8% had a female householder with no husband present, 29.5% were non-families, and 25.9% of all households were made up of individuals. The average household size was 2.56 and the average family size was 3.04. The median age was 40.3 years.

The median income for a household in the county was $32,743 and the median income for a family was $42,074. Males had a median income of $39,008 versus $27,701 for females. The per capita income for the county was $17,687. About 18.6% of families and 21.4% of the population were below the poverty line, including 30.0% of those under age 18 and 18.0% of those age 65 or over.

At the 2000 census, there were 34,068 people, 12,880 households, and 9,338 families living in the county. The population density was 59 people per square mile (23 people/km). There were 14,374 housing units at an average density of 25 units per square mile (9.7 units/km). The racial makeup of the county was 59.93% White, 38.65% Black or African American, 0.33% Native American, 0.28% Asian, 0.01% Pacific Islander, 0.25% from other races, and 0.55% from two or more races. 0.75% of the population were Hispanic or Latino of any race.

There were 12,880 households, out of which 32.90% had children under the age of 18 living with them, 48.80% were married couples living together, 18.60% had a female householder with no husband present, and 27.50% were non-families. 24.20% of all households were made up of individuals, and 9.90% had someone living alone who was 65 years of age or older. The average household size was 2.62 and the average family size was 3.11.

In the county, the population was spread out, with 26.90% under the age of 18, 8.40% from 18 to 24, 28.20% from 25 to 44, 23.80% from 45 to 64, and 12.70% who were 65 years of age or older. The median age was 36 years. For every 100 females there were 92.50 males. For every 100 females age 18 and over, there were 87.60 males.

The median income for a household in the county was $32,425, and the median income for a family was $38,087. Males had a median income of $30,329 versus $21,570 for females. The per capita income for the county was $14,709. About 11.90% of families and 15.30% of the population were below the poverty line, including 21.20% of those under age 18 and 14.90% of those age 65 or over.

In 2021, Chester County Sheriff Alex Underwood was found guilty of conspiracy, wire fraud, deprivation of rights and federal program theft, and sentenced to one year in prison.

Chester County's economy has an industrial and agricultural base with large areas used for timber production. There are several sawmills in the county and others near it. Forest land ownership is majority family landowners who manage their properties for a variety of uses. Agriculture is also a big segment of the economy with crops consisting of cotton, wheat, oats, rye, beef and dairy cattle, hay, corn, peaches, other vegetables, peanuts, soybeans, and pecans.

In 2022, the GDP of Chester County was $1.4 billion (about $43,999 per capita). In chained 2017 dollars, its real GDP was $1.1 billion (about $35,382 per capita). Throughout 2022 to 2024, the unemployment rate has fluctuated between 3.1% and 5.6%.

As of April 2024, some of the largest employers in the county include Chester County School District, E & J Gallo Winery, and Walmart.

• Chester Vision or CSN
• Chester News & Reporter
• WRBK, 90.3 FM, a noncommercial station that primarily features classic oldies

• Chester (county seat and largest community)

• Fort Lawn
• Great Falls
• Lowrys
• Richburg

• Eureka Mill
• Gayle Mill

• Blackstock
• Edgemoor
• Lando
• Leeds
• Wilksburg

• John Adair, (1757–1840), born in Chester County (although at the time it was believed to be part of Anson County, North Carolina), became a member of the United States House of Representatives and the United States Senate, and the 8th governor of Kentucky
• Thomas Griffin and Meeks Griffin, were wrongly executed in South Carolina by electric chair in 1915. They were framed in Chester County in 1913 and pardoned in 2009.

• List of counties in South Carolina
• National Register of Historic Places listings in Chester County, South Carolina
• Tryon County, North Carolina, former county in North Carolina which included modern-day parts of Chester County

Wikimedia Commons has media related to Chester County, South Carolina.

• Geographic data related to Chester County, South Carolina at OpenStreetMap
• Official website
• Chester County history and images