Somerset County, New Jersey
Founded on May 14, 1688, from portions of Middlesex County, Somerset County is a distinguished region of New Jersey named after the English county of Somerset. With its county seat in Somerville, the area has evolved from its colonial roots into one of the most affluent and highly educated regions in the United States.
The county balances a rich historical legacy with modern economic power, consistently ranking as a leader in per capita income and educational attainment. From the sprawling landscapes of its townships to the bustling centers of its boroughs, Somerset County represents a blend of suburban comfort and professional excellence.
Key Facts
- Founded: May 14, 1688.
- County Seat: Somerville.
- Population: 345,361 (2020 Census), with a 2025 estimate of 356,486.
- Economic Standing: Highest per capita income in New Jersey (as of 2009) and the highest GDP in America for counties with populations between 100,000 and 500,000 (as of 2023).
- Education: Highest percentage of college graduates in New Jersey (49.8% in 2012).
- Geography: Total area of 304.95 square miles, with Hillsborough Township being the largest by area and Franklin Township the largest by population.
Economic Profile and Wealth
Somerset County is recognized as a powerhouse of economic prosperity. In 2015, the per capita personal income reached $86,468, ranking it 25th among all 3,113 counties in the United States and second highest in New Jersey. Historically, the county has maintained this trajectory; the 2000 Census ranked it as the seventh wealthiest county in the U.S. by median household income ($76,933).
The region's economic strength is further evidenced by its GDP. As of 2023, Somerset County held the highest GDP in the United States for counties within the 100,000 to 500,000 population bracket.
Demographics and Education
The population of Somerset County has seen steady growth, rising from just over 12,000 in 1790 to over 345,000 by 2020. The 2020 Census reported a median age of 42.0 years, with a diverse racial and ethnic composition that has shifted significantly over the decades. Notably, the Asian population grew from 1.39% in 1980 to 19.43% in 2020, and the Hispanic or Latino population increased from 2.01% to 16.61% in the same period.
Education is a cornerstone of the community. In 2012, nearly half of the residents (49.8%) were college graduates, the highest rate in the state. This commitment to learning is supported by a comprehensive network of K-12 school districts, including the Bridgewater-Raritan Regional and Somerset Hills districts, as well as various vocational and technical schools.
Geography and Infrastructure
Covering 304.95 square miles, the county is primarily land (301.87 sq mi), with water making up approximately 1% of its total area. The landscape is dotted with scenic trails and preserves that offer residents a reprieve from suburban life.
The county's infrastructure includes over 1,700 miles of roadways. While a plan for the Somerset Freeway (Interstate 95) was proposed in the 1960s to connect Mercer County to Franklin Township, the project was ultimately canceled in 1983. Today, the region is served by a mix of local, county, and state-maintained roads, including Route 18 along the New Brunswick border.
Public transportation is facilitated through various rail and bus connections, with key hubs like the Bernardsville station serving the community.
County Administration and Governance
Somerset County is governed by a Board of County Commissioners, currently led by Commissioner Director Shanel Robinson (term ending December 31, 2026). On a federal level, the county is split between the 7th Congressional District, represented by Thomas Kean Jr., and the 12th Congressional District, represented by Bonnie Watson Coleman.
Municipal Overview
The county is divided into various townships and boroughs, each contributing to the region's overall character. The following table summarizes key data for selected municipalities.
| Municipality | Type | Population (2020) | Land Area (sq mi) | Pop. Density (per sq mi) |
|---|---|---|---|---|
| Franklin Township | Township | 68,364 | 46.15 | 1,350.0 |
| Bridgewater Township | Township | 45,977 | 32.04 | 1,387.9 |
| Hillsborough Township | Township | 43,276 | 54.54 | 702.3 |
| Bernards Township | Township | 27,830 | 23.93 | 1,113.6 |
| Somerville | Borough | 12,346 | 2.33 | 5,189.5 |
Frequently Asked Questions
What is the largest municipality in Somerset County?
Franklin Township is the largest municipality by population, while Hillsborough Township is the largest in terms of total land area.
How does Somerset County rank in terms of wealth?
The county is one of the wealthiest in the U.S. and New Jersey. As of 2009, it had the highest per capita income in New Jersey, and as of 2023, it had the highest GDP for U.S. counties with populations between 100,000 and 500,000.
What is the educational attainment level in the county?
Somerset County is highly educated; as of 2012, it had the highest percentage of college graduates in New Jersey at 49.8%.
Who represents Somerset County in the U.S. Congress?
The county is served by two representatives: Thomas Kean Jr. for the 7th Congressional District and Bonnie Watson Coleman for the 12th Congressional District.
When was Somerset County established?
Somerset County was created on May 14, 1688, from portions of Middlesex County.