According to the United States Census Bureau, the city has a total area of 4.8 square miles (12.5 km²), of which, 4.8 square miles (12.5 km²) of it is land and 0.21% is water.
Dillon gained prosperity when the town's founding fathers allowed the railroad to come through it. Little Rock, (a smaller, neighboring town) was the original choice, but its residents believed the railroad would do more harm than good.
Dillon had the good fortune of being located along a frequently-used railway line, and was at one time a prosperous town, as evidenced by its large and ornate courthouse. Its economy was based on the profitable tobacco- and cotton-production and sales industries, a source of income that has slowly shrunk over the years as production and transport systems for these commodities have become more efficient and less centralized. Now, outside of service industry and state jobs, gainful employment is scarce in Dillon. Despite this, the city infrastructure is well-maintained and there is a large, modern hosital and medical complex--Formerly Saint Eugene Hospital, now McLeod Medical Center of Dillon and a city-owned . Wellness Center that has over 900 members, which was open in March 2007.
The City of Dillon's population has remained at about 7,000 since the early 1970s, meaning that its population has steadily shrunk proportionally to South Carolina as a whole. The city is a good example of an economic situation found in many smaller cities and towns throughout the United States, in that its geography once made it important in the local/regional economy, but with changes in agriculture, the rise of the interstate highways and interstate trucking, globalization, and the information economy, it has become more or less defunct as an economic entity.
Dillon is home to the second largest yarn producing factory in the United States. In early 2007 the factory, and it's textile division, was sold by Dillon Yarn Corporation to yarn powerhouse Unifi. The other Dillon divisions continued to run in the factory. After Unifi shut the factory down, an affiliate of Dillon Yarn Corporation decided to buy back the factory keeping the existing Dillon divisions in place.
In 2001, Harbor Freight Tools, a California-based tool retailer, built a large distribution center near Dillon, bringing many much-needed jobs to the city.
Interstate 95 and South Carolina Highway 9 intersect at Exit 193, with Highway 9 passing through the heart of downtown and becoming part of Main Street for a few miles. Exit 193 is the Exit most used by travelers to Myrtle Beach, South Carolina, a popular vacation spot.
Exit 190, Dillon's second and more-used I-95 exit, was recently named after the Honorable William James "Bill" McLeod, Sr., a WWII veteran, former state representative, and retired family court judge.
Dillon also is home to Twin Lakes Country Club. The overpass overlooking the golf course and the once famous rail line is named after William Bledsoe (W.B.) Hawkins, a former state representative, WWII veteran, and respected attorney.
Dillon High School has about 1,000 students. Its mascot is the Dillon Wildcat and its colors are black and gold. Football is the most popular sport; in the two years after the departure of tenured coach Paul A. Chapman in 1989, the Wildcats' performance was lackluster at best, but the arrival of former assistant sixth grade PE coach Jackie Hayes in 1992 launched a football juggernaut.
There were 2,511 households out of which 30.2% had children under the age of 18 living with them, 39.4% were married couples living together, 22.3% had a female householder with no husband present, and 34.3% were non-families. 30.8% of all households were made up of individuals and 14.3% had someone living alone who was 65 years of age or older. The average household size was 2.48 and the average family size was 3.12.
In the city the population was spread out with 27.6% under the age of 18, 8.2% from 18 to 24, 24.2% from 25 to 44, 23.5% from 45 to 64, and 16.4% who were 65 years of age or older. The median age was 38 years. For every 100 females there were 80.4 males. For every 100 females age 18 and over, there were 72.8 males.
The median income for a household in the city was $25,267, and the median income for a family was $34,758. Males had a median income of $26,897 versus $19,031 for females. The per capita income for the city was $15,075. About 20.0% of families and 26.0% of the population were below the poverty line, including 36.2% of those under age 18 and 26.9% of those age 65 or over.