Somerset County, New Jersey population

County or county equivalent · Official geographic code 34035

356,486

· Annual resident population estimate

U.S. Census Bureau · Population Estimates Program · Vintage 2025

+1,364 residents (+0.38%) since July 1, 2024.

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Population change, 2020–2025
+11,970July 1 to July 1 · +3.47%
Land-area density, 2025
1,180.9People per square mile · 2025 land area
Population rank, 2025
213 of 3,144U.S. counties and county equivalents

Somerset County population history

Open historical explorer

These six July 1 estimates belong to one consistent Vintage 2025 series. The Census Bureau revises earlier years when it releases a new vintage; a figure from an older publication may differ from the value below.

Annual resident population estimates, July 1, 2020–2025; Vintage 20252020: 344,516 people; 2021: 346,069 people; 2022: 347,621 people; 2023: 351,042 people; 2024: 355,122 people; 2025: 356,486 people 358.3k349.9k341.5k 202020212022202320242025

Annual estimates · 2020–2025 · Vertical scale shown on chart.

The highest observed population in this annual series was 356,486 in 2025. This is a peak within 2020–2025 coverage, not an all-time record.

Somerset County, New Jersey: July 1 annual population estimates, Vintage 2025
Reference datePopulationAnnual change
July 1, 2020344,516—
July 1, 2021346,069+1,553
July 1, 2022347,621+1,552
July 1, 2023351,042+3,421
July 1, 2024355,122+4,080
July 1, 2025356,486+1,364
Why is the April 2020 estimates base different from a census count?

The PEP estimates base here is 345,349 residents on April 1, 2020. It incorporates the Census Bureau’s corrections and geographic revisions and serves as the starting point for this annual series. It is not labeled an original 2020 census count. The chart starts at July 1, 2020, so its five-year change uses two July observations. Read about measurement types.

Growth and density

Between July 1, 2020 and July 1, 2025, Somerset County gained 11,970 residents, a 3.47% increase. The annualized change over these five elapsed years was +0.69%. Annualized change is a summary of the interval; it does not imply that the population changed at that rate in every year.

The 2025 Gazetteer reports 301.87 square miles of land. Dividing the July 1, 2025 population by that compatible land area gives 1,180.9 people per square mile. Water area is excluded. Density depends on geographic boundaries. It describes this entire geography, rather than a typical neighborhood or built-up area.

Calculations use unrounded source values. Population counts are displayed as integers, percentages to two decimals and density to one decimal. Calculation methods · Growth calculator

Components of population change

The published components cover July 1, 2024 through June 30, 2025. Natural change equals births minus deaths. Net migration is arrivals minus departures; it does not establish why people moved.

Natural change
+740
Net domestic migration
-1,362
Net international migration
+1,977
Residual
+9
Source-published components, annual interval ending June 30, 2025
ComponentPeople
Births3,311
Deaths2,571
Natural change+740
Net domestic migration-1,362
Net international migration+1,977
Residual+9
Total population change+1,364

Reconciliation: natural change + net domestic migration + net international migration + residual = +1,364. Births and deaths are already included in natural change and must not be added again. Source: co-est2025-alldata.csv; Vintage 2025.

Age structure, race and Hispanic-origin panels are not included in this totals release. Their separate periods, definitions and uncertainty will be validated before publication. Coverage details.

Geographic context

County equivalents include parishes, boroughs, census areas, independent cities, DC and Connecticut planning regions where represented by Census. The places listed below are whole-city observations and can extend into other counties. Summing them will not reproduce this county total.

Resident population, July 1, 2025; change since July 1, 2024. PEP Vintage 2025.
PlacePopulation · 2025Change · 2024–25Growth · 2024–25People / sq. mi.
North PlainfieldNew Jersey · Incorporated place · 345328022,879-49-0.21%8,149.4
SomervilleNew Jersey · Incorporated place · 346846014,665+322+2.24%6,273.2
Bound BrookNew Jersey · Incorporated place · 340679013,038+469+3.73%7,848.1
ManvilleNew Jersey · Incorporated place · 344362010,932-23-0.21%4,630.4
RaritanNew Jersey · Incorporated place · 34619808,516-12-0.14%4,275.4
BernardsvilleNew Jersey · Incorporated place · 34055907,966+7+0.09%620.6
WatchungNew Jersey · Incorporated place · 34776006,583-17-0.26%1,094.3
South Bound BrookNew Jersey · Incorporated place · 34687304,926-11-0.22%7,641.1
Peapack and GladstoneNew Jersey · Incorporated place · 34573002,587-3-0.12%451.3
Far HillsNew Jersey · Incorporated place · 3422890974+40+4.28%201.0

Showing 10 of 12 related records.

New Jersey population · State city directory · City proper versus county versus metro

Places with nearby population ranks

Selected from the same 2025 comparison universe, using neighboring population ranks. Similar population does not imply similar density, boundaries or demographics.

Resident population, July 1, 2025; change since July 1, 2024. PEP Vintage 2025.
PlacePopulation · 2025Change · 2024–25Growth · 2024–25People / sq. mi.
Orleans ParishLouisiana · County equivalent · 22071362,154-1,323-0.36%2,135.6
Rockland CountyNew York · County equivalent · 36087357,397+2,568+0.72%2,057.7
Marion CountyOregon · County equivalent · 41047355,777+2,559+0.72%301.3
Nueces CountyTexas · County equivalent · 48355352,992+67+0.02%420.5

Source, citation and downloads

U.S. Census Bureau, Population Estimates Program, Vintage 2025, co-est2025-alldata.csv, variable POPESTIMATE2025; Somerset County, New Jersey, geographic code 34035; resident population 356,486 on July 1, 2025; boundaries January 1, 2025. https://www2.census.gov/programs-surveys/popest/datasets/2020-2025/counties/totals/co-est2025-alldata.csv. Retrieved September 30, 2026. US Population Data snapshot pep-2025-r1, transformation 1.

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