Overton lies in two counties as well as two metropolitan areas. The Rusk County portion of the city is part of the Longview Metropolitan Statistical Area, while the Smith County portion is part of the Tyler Metropolitan Statistical Area.
According to the United States Census Bureau, the city has a total area of 6.8 square miles (17.5 km²), of which, 6.7 square miles (17.4 km²) of it is land and 0.04 square miles (0.1 km²) of it (0.59%) is water. Most of the city lies in Rusk County, with only a small part extending into Smith County.
There were 906 households out of which 31.2% had children under the age of 18 living with them, 53.2% were married couples living together, 12.1% had a female householder with no husband present, and 30.5% were non-families. 27.7% of all households were made up of individuals and 15.3% had someone living alone who was 65 years of age or older. The average household size was 2.45 and the average family size was 2.99.
In the city the population was spread out with 25.7% under the age of 18, 8.4% from 18 to 24, 24.6% from 25 to 44, 22.0% from 45 to 64, and 19.2% who were 65 years of age or older. The median age was 38 years. For every 100 females there were 87.5 males. For every 100 females age 18 and over, there were 89.3 males.
The median income for a household in the city was $28,098, and the median income for a family was $34,662. Males had a median income of $30,329 versus $17,255 for females. The per capita income for the city was $17,256. About 14.1% of families and 17.5% of the population were below the poverty line, including 24.8% of those under age 18 and 14.4% of those age 65 or over.
Overton was originally intended to be a crossroads for two railroads. In 1875 the Henderson and Overton Branch Railroad, 16 miles long, was completed and was later joined by the International-Great Northern. When the nearby towns of Rocky Mount, Belleview, and Jamestown were all bypassed by the railroad, Overton gained the businesses and people who wanted to benefit from the railroad lines. The town offered lots for businesses to relocate and many took the offer.
The Masons and Odd Fellows built the first school and a church was constructed in 1875. By 1888 the population had increased to 500 and had all essential businesses, including a newspaper. Overton prospered as an agricultural community and in 1904 the population had reached 568.
Oklahoman wildcatter C. M. (Dad) Joiner was drilling his third well in 1930 and the town of Overton helped raise the funds he needed to drill. When the well came in - Overton shared in Joiner's success. Churches, schools, and a refinery were built. Hubbard College was founded during this time as well. The towns economy suddenly revolved around the production of oil.
Overton's population exploded from 426 in 1931 to 3,000 in 1933. By 1936 it was up to 4,500 and the town went through the Great Depression relatively unscathed. But by the end of WWII the population had declined by half - reaching just 2,000 in the fifties and remaining at that level through the 70s. In the 1980s Overton was Rusk County's "second city" with a population of 2,430 in 1983. By the 1990s Overton extended into neighboring Smith County.