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Mercer County, NJ
18 cities and towns and 22 ZIP codes in Mercer County, New Jersey.
Population
385,864
Land area
224sq mi
People per sq mi
1,719
ZIP codes
22
Cities and towns in Mercer County
Mercer County at a glance
- Mercer County is 35% denser than New Jersey as a whole.
- The median household income is $100,645, close to the New Jersey median.
- A typical owner-occupied home is valued at $377,700 (17% below New Jersey) and median rent is $1,623 a month.
- Its largest cities are Trenton (90,338), Princeton (30,756) and Mercerville (13,535).
Local data for Mercer County, NJ
Counts from official public data
- Hospitals3
- Emergency Rooms3
- Nursing Homes15
- Schools144
- Colleges11
- Libraries14
- Banks100
- Post Offices18
- Parks194
- Grocery Stores174
- Restaurants1,351
- Affordable Housing47
- Hospice Care2
- Dialysis Centers8
- Rehab & Long-Term Care Hospitals1
- Community Health Centers10
- Mental Health & Addiction Treatment33
- Private Schools35
- Community Colleges & Trade Schools6
- Superfund Sites1
- Toxic Release Facilities8
- Historic Places67
Housing and community stats
Mercer County, NJ, American Community Survey 2020-2024
Median household income
$100,645
Poverty rate
10.3%
Median home value
$377,700
Prices +5.7% in a year
Median rent
$1,623/mo
Homeownership
62.2%
Bachelor's or higher
45.4%
Median age
39.5
Average commute
27.1 min
Largest reported origins and ancestries: Italian Americans (39,398), Irish Americans (37,770), German Americans (32,190).
Economy and federal money
Jobs, income, federal spending and pandemic loans
Unemployment rate
4.9%
Aug 2026, -1.1 pts in a year
Average annual pay
$94,418
261,312 jobs, 2025
Income per person
$87,068
BEA, 2024
Federal spending
$4.71B
FY 2026, $12,169 per person
PPP loans
$1.22B
12,131 loans, 117,375 jobs reported
Campaign donations
$6.12M
Itemized, 2026 cycle
How people get to work
Mercer County, NJ, workers 16 and older. American Community Survey 5-year estimates
- Drove alone60.2%
- Carpooled8.7%
- Public transit4.6%
- Walked3.6%
- Bicycle0.6%
- Taxi, ride-hailing, motorcycle or other2.7%
- Worked from home19.5%
Average one-way commute: 27.1 minutes for people who do not work from home.
Environment and hazard risk
Mercer County, NJ, from FEMA, NOAA and EPA
Natural hazard risk
Relatively High
Top: strong wind
Storm events since 1996
1,115
Most often thunderstorm wind
Flood insurance policies
1,294
1.2% of homes, county
July high / Jan low
87° / 23°F
47.3 inches of rain a year
Hazards, floods and storm historyCheck a flood zone67 historic places
Health statistics
Share of adults in Mercer County, NJ, CDC PLACES estimates
Obesity
25.4%
U.S. 33.3% -7.9 pts
Diabetes
11.1%
U.S. 12.1% -1.0 pts
Smoking
10.5%
U.S. 12.8% -2.3 pts
Uninsured (18-64)
11.4%
U.S. 11.1% about the same
Cities, towns and ZIP codes in Mercer County
Population shown
- Trenton90,338
- Princeton30,756
- Mercerville13,535
- Hamilton Square11,622
- White Horse10,507
- Twin Rivers8,382
- Yardville6,301
- Hightstown5,920
- Lawrenceville3,924
- Robbinsville Center3,777
- The College of New Jersey3,658
- Groveville3,100
- Pennington2,827
- Princeton Junction2,025
- Hopewell1,823
- Washington Crossing536
- Titusville501
- Windsor325
Frequently asked questions
- What is the largest city in Mercer County, NJ?
- Trenton is the largest city or town in Mercer County, with about 90,338 residents.
- How many ZIP codes are in Mercer County?
- Mercer County includes 22 ZIP Code Tabulation Areas, including 08520, 08525, 08534, 08540, 08542.
- What is the population of Mercer County, NJ?
- About 385,864 people live in Mercer County, based on American Community Survey 5-year estimates.
- What counties border Mercer County?
- Mercer County borders Middlesex County, Bucks County, PA, Monmouth County, Burlington County, Somerset County, Hunterdon County.
Source: U.S. Census Bureau (TIGER/Line boundaries, American Community Survey) · Data as of 12/31/2023