Jefferson County, Kentucky

Jefferson County
Jefferson County Courthouse (now Louisville Metro Hall) in downtown Louisville
Jefferson County Courthouse (now Louisville Metro Hall) in downtown Louisville
Official seal of Jefferson County
Map of Kentucky highlighting Jefferson County
Location within the U.S. state of Kentucky
Map of the United States highlighting Kentucky
Kentucky's location within the U.S.
Coordinates: 38°11′N 85°40′W / 38.19°N 85.66°W / 38.19; -85.66
Country United States
State Kentucky
Founded1780
Named forThomas Jefferson
SeatLouisville
Largest cityLouisville
Area
 • Total398 sq mi (1,030 km2)
 • Land380 sq mi (1,000 km2)
 • Water17 sq mi (40 km2)  4.3%
Population
 (2020)
 • Total782,969
 • Estimate 
(2023)
772,144 Decrease
 • Density2,000/sq mi (760/km2)
Time zoneUTC−5 (Eastern)
 • Summer (DST)UTC−4 (EDT)
Congressional districts3rd, 2nd
Websitelouisvilleky.gov

Jefferson County is a county located in the north central portion of the U.S. state of Kentucky. As of the 2020 census, the population was 782,969.[1] It is the most populous county in the commonwealth (with more than twice the population of second ranked Fayette County).

Since a city-county merger in 2003, the county's territory, population and government have been coextensive with the city of Louisville, which also serves as county seat. The administrative entity created by this merger is the Louisville/Jefferson County Metro Government,[2] abbreviated to Louisville Metro.[3]

Jefferson County is the anchor of the Louisville-Jefferson County, KY-IN Metropolitan Statistical Area, locally referred to as Kentuckiana.

  1. ^ "State & County QuickFacts". United States Census Bureau. Archived from the original on May 17, 2022. Retrieved June 28, 2022.
  2. ^ "Louisville/Jefferson County Metro Government Code of Ordinances". American Legal Publishing Corporation. Archived from the original on July 1, 2014. Retrieved August 19, 2014.
  3. ^ "Louisville/Jefferson County Metro Government Code of Ordinances § 10.06 DEFINITIONS". American Legal Publishing Corporation. Archived from the original on August 20, 2014. Retrieved August 19, 2014.