Thomas County was created by an act of theGeorgia General Assembly on December 23, 1825, from portions ofDecatur andIrwin Counties.[3]Colquitt (1856),Brooks (1858), andGrady (1905) Counties all were formed partially from lands within Thomas County's original borders.
The county is named forJett Thomas, an officer in theWar of 1812 who is also known for overseeing the construction of the first building at theUniversity of Georgia (originally referred to as Franklin College and known today as Old College) as well as the state capital atMilledgeville.
According to theU.S. Census Bureau, the county has a total area of 552 square miles (1,430 km2), of which 545 square miles (1,410 km2) is land and 7.6 square miles (20 km2) (1.4%) is water.[4]
The northwestern half of Thomas County, bordered byU.S. Route 319 southwest ofThomasville, and a line that ends up bisecting the distance betweenCoolidge andPavo in the northeast, is located in the UpperOchlockonee River sub-basin of the larger Ochlockonee River basin. The northeastern edge of the county, from north of Pavo toBoston, is located in theWithlacoochee River sub-basin of theSuwannee River basin. The southeastern portion of Thomas County, running southeast from Thomasville, is located in theAucilla River sub-basin of the larger Aucilla-Waccasassa basin. Almost all of the southwestern portion of the county is located in theApalachee Bay-St. Marks sub-basin of the Ochlockonee River basin, with the exception of the tiny southwesternmost corner, which is located in the LowerOchlockonee River sub-basin of the same Ochlockonee River basin.[5]
As of the2020 census, the county had a population of 45,798 in 18,440 households, including 12,161 families.[17]
The median age was 40.8 years. 23.5% of residents were under the age of 18 and 19.0% of residents were 65 years of age or older. For every 100 females there were 90.0 males, and for every 100 females age 18 and over there were 85.6 males age 18 and over.[18]
55.1% of residents lived in urban areas, while 44.9% lived in rural areas.[18]
Among those households, 30.6% had children under the age of 18 living with them and 34.1% had a female householder with no spouse or partner present. About 29.1% of all households were made up of individuals and 13.4% had someone living alone who was 65 years of age or older.[17]
There were 20,668 housing units, of which 10.8% were vacant. Among occupied housing units, 63.5% were owner-occupied and 36.5% were renter-occupied. The homeowner vacancy rate was 1.6% and the rental vacancy rate was 6.3%.[17]