States · New Jersey · Mercer County

Princeton Junction, New Jersey.

A community in Mercer County, with no city government of its own. Zillow publishes no home prices for it: see Mercer County’s.

Living in Princeton Junction, Mercer County, New Jersey

Princeton Junction, in Mercer County, had 2,475 people in the 2020 census. 82% of its homes are lived in by their owners and 18% are rented. Unemployment in Mercer County was 4.9% in August 2026, and the county had 1.1% fewer jobs in 2025 than the year before. The most people in Mercer County work in schools and health care, then professional services.

People 2,475 in the 2020 census
Household income Too few homes in Princeton Junction for the Census survey to measure.
Unemployment 4.9% Mercer County, August 2026; 6.0% a year before
Homes 82% lived in by their owners; 18% rented
  • 795households
  • 79%of adults have a degree
  • 8%below the poverty line

What people in Mercer County work in

  • Schools, hospitals and social care26%
  • Professional and business services14%
  • Shops (retail)9%
  • Banks, insurance and property8%
  • Manufacturing8%
  • Restaurants, hotels and entertainment7%

Employed residents by industry, from the Census survey. Mercer County had 261,312 jobs in 2025, 1.1% fewer than the year before (Bureau of Labor Statistics).

Weather through the year

Average daily high and low for each month: coldest in January, 40° and 21°; warmest in July, 87° and 63° 20° 40° 60° 80° J 40° 21° F M A M J J 87° 63° A S O N D
Average daily high and low for each month: coldest in January, 40° and 21°; warmest in July, 87° and 63° 20° 40° 60° 80° J 40° 21° F M A M J J 87° 63° A S O N D

Coldest in January, with highs near 40° and lows near 21°; warmest in July, with highs near 87° and lows near 63°. About 24 inches of snow and 47 inches of rain and melted snow a year.

Average daily high and low, 1991–2020, at the Hightstown West weather station, 5 miles away (NOAA).

Largest workplaces in Mercer County

  1. Princeton UniversityUniversity or college7,778
  2. Johnson JohnsonPharmaceutical4,059
  3. AmazonGeneral warehousing and storage3,337
  4. Capital Health MED Center - HopewellGeneral hospital3,052FTE
  5. Otsuka America Pharmaceutical, Inc. (OAPI)Druggists' sundries merchant wholesalers2,077
  6. Capital Health Regional Medical CTRGeneral hospital2,003FTE
  7. Hamilton Township Public School DistrictSchool district1,811FTE
  8. Trenton Public School DistrictSchool district1,691FTE

Staff on average in 2025, as each workplace reported it to OSHA with its injury records: 265 workplaces with 20 or more staff, 49,148 people in all across the county; Princeton Junction has one of its own. Colleges come from IPEDS (NCES, 2023–24), hospitals from their Medicare cost reports (CMS, 2023) and school districts from the Common Core of Data (NCES, 2023–24); FTE marks full-time equivalent staff. Not listed: many offices and banks, which need not report to OSHA; military bases, whose staff OPM withholds; and, in about half the states, city and county governments.

Natural hazards

  1. Strong windRelatively high
  2. Inland floodingRelatively high
  3. Winter weatherRelatively high
  4. Ice stormsrelatively high in parts of Princeton JunctionRelatively moderate
  5. HurricanesRelatively moderate
  6. Heat wavesRelatively moderate

FEMA’s National Risk Index (December 2025) rates the risk each natural hazard poses to the people, buildings and farms in Princeton Junction’s census tracts, against the rest of the country; all of them together, relatively moderate. It is meant for planning, not a substitute for a local risk assessment or a flood map: FEMA’s index.

From the U.S. Census Bureau’s 2020 census and its American Community Survey (2020–2024 five-year estimates), and the Bureau of Labor Statistics. A survey, so each figure has a margin of error, and figures it is not sure of are left out. More on Mercer County.