Somerset County, New Jersey

Somerset County
Location within the U.S. state of New Jersey
New Jersey's location within the U.S.
Coordinates: 40°34′N 74°37′W / 40.56°N 74.61°W / 40.56; -74.61
Country United States
State New Jersey
FoundedMay 14, 1688
Named afterEnglish county of Somerset
SeatSomerville
Largest municipalityFranklin Township (population)
Hillsborough Township (area)
Government
  Commissioner directorShanel Robinson (D, term ends December 31, 2023)
Area
  Total
304.95 sq mi (789.8 km2)
  Land301.87 sq mi (781.8 km2)
  Water3.09 sq mi (8.0 km2)  1.00%
Population
 (2020)
  Total
345,361
  Estimate 
(2024)
357,467
  Density1,100/sq mi (440/km2)
Time zoneUTC−5 (Eastern)
  Summer (DST)UTC−4 (EDT)
Congressional districts7th, 12th
Websiteco.somerset.nj.us

Somerset County is a county located in the north-central part of the U.S. state of New Jersey. As of the 2020 census, the county was the state's 13th-most-populous county, with a population of 345,361, its highest decennial count ever and an increase of 21,917 (+6.8%) from the 2010 census count of 323,444. Somerset County constitutes part of the New York metropolitan area. Its county seat is Somerville. The most populous place in the county was Franklin Township, with 68,364 residents at the time of the 2020 census, while Hillsborough Township, with 55.00 square miles (142.4 km2), covered the largest total area of any municipality. The county is part of the Central Jersey region of the state.

In 2012, 49.8 percent of Somerset County residents were college graduates, the highest percentage in the state. Somerset County was recently ranked number 3 of 21 NJ counties as one of the healthiest counties in New Jersey, according to an annual report by County Health Rankings and Roadmaps. Somerset County was created on May 14, 1688, from portions of Middlesex County.