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ZIP codes

ZIP codes in Mercer County, New Jersey

Mercer County has 26 ZIP codes. 16 lie entirely inside it and 10 are shared with neighboring counties, so part of their land and their people are elsewhere. About 381,115 people live in the parts inside it (ACS 2020–2024).

By the All Map Tools Team

ZIP codes
26
With 1% or more of their land inside
Entirely inside
16
99% or more of their land
Shared with other counties
10
Most with Burlington County (3)
Most populated ZIP
08540
50,388 people · Princeton
Least populated ZIP
08561
325 people · Windsor
Largest ZIP by land
08540
52 sq mi · Princeton

Map of the ZIP codes in Mercer County

Burlington County Hunterdon County Middlesex County Monmouth County Somerset County Bucks County, PA 08501 · Allentown · 6,364 people · 3.0% in the county 08512 · Cranbury · 12,928 people · 6.7% in the county 08520 · Twin Rivers · 29,504 people · 100% in the county 08525 · Hopewell · 4,522 people · 70% in the county 08530 · Lambertville · 8,119 people · 19% in the county 08534 · Pennington · 13,272 people · 100% in the county 08540 · Princeton · 50,388 people · 63% in the county 08542 · Princeton · 2,533 people · 100% in the county 08544 · Princeton · 4,392 people · 100% in the county 08550 · Princeton Junction · 21,067 people · 100% in the county 08558 · Skillman · 7,648 people · 4.6% in the county 08560 · Titusville · 3,245 people · 99% in the county 08561 · Windsor · 325 people · 100% in the county 08608 · Trenton · 1,250 people · 100% in the county 08609 · Trenton · 15,938 people · 100% in the county 08610 · White Horse · 33,465 people · 94% in the county 08611 · Trenton · 31,995 people · 100% in the county 08618 · Trenton · 35,634 people · 100% in the county 08619 · Mercerville · 24,089 people · 100% in the county 08620 · Yardville · 11,621 people · 87% in the county 08628 · Trenton · 9,831 people · 100% in the county 08629 · Trenton · 13,013 people · 100% in the county 08638 · Trenton · 22,816 people · 100% in the county 08648 · Lawrenceville · 31,323 people · 100% in the county 08690 · Hamilton Square · 18,841 people · 100% in the county 08691 · Yardville · 16,607 people · 89% in the county
  • Entirely in the county (99% or more of its land)
  • Shared, mostly in this county
  • Shared, mostly in other counties
  • Neighboring counties
Open in the interactive tool

Each area is a ZIP code with its number where it fits. Hover over one to see its name.

All ZIP codes in Mercer County

26 ZIP codes in Mercer County, NJ, by number
ZIP code Main city Population Land in the county Residents in the county
08501 Allentown 6,364 3.0% ≈ 455
08512 Cranbury 12,928 6.7% ≈ 2,931
08520 Twin Rivers 29,504 100% 29,504
08525 Hopewell 4,522 70% ≈ 3,809
08530 Lambertville 8,119 19% ≈ 1,158
08534 Pennington 13,272 100% 13,272
08540 Princeton 50,388 63% ≈ 35,190
08542 Princeton 2,533 100% 2,533
08544 Princeton 4,392 100% 4,392
08550 Princeton Junction 21,067 100% 21,067
08558 Skillman 7,648 4.6% ≈ 149
08560 Titusville 3,245 99% ≈ 3,223
08561 Windsor 325 100% 325
08608 Trenton 1,250 100% 1,250
08609 Trenton 15,938 100% 15,938
08610 White Horse 33,465 94% ≈ 32,753
08611 Trenton 31,995 100% 31,995
08618 Trenton 35,634 100% 35,634
08619 Mercerville 24,089 100% 24,089
08620 Yardville 11,621 87% ≈ 9,379
08628 Trenton 9,831 100% 9,831
08629 Trenton 13,013 100% 13,013
08638 Trenton 22,816 100% 22,816
08648 Lawrenceville 31,323 100% 31,323
08690 Hamilton Square 18,841 100% 18,841
08691 Yardville 16,607 89% ≈ 16,245

ZIP codes shared with other counties

These 10 ZIP codes have part of their land in another county. The first figure is the share of their land in Mercer County; then, where the rest lies.

Cities and prefixes

By main city (the city, town or CDP each ZIP shares the most land with), the ones with the most are Trenton (7), Princeton (3), Yardville (2), Allentown (1), Cranbury (1), and Hamilton Square (1); 17 places in all.

They start with 2 different three-digit prefixes, one per USPS sorting center: 085 and 086.

Neighboring counties

Each one with its ZIP codes. Those without a page of their own open in the tool.

Tools for this county

ZIP codes by county or city The same ZIP codes on an interactive map, with the list as CSV or to copy County map with cities Its cities, towns and CDPs with their population ZIP codes in a radius The ZIP codes within 10 miles of its center, or any distance you like

Sources

  • U.S. Census Bureau, 2020 ZCTA to County, ZCTA to Place and ZCTA to Census Tract Relationship Files (and the 2022 County Subdivision to ZCTA file for Connecticut). Public domain.
  • U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates, table B01003 (population of each ZIP code, census tract and Connecticut town). Public domain.
  • U.S. Census Bureau, Vintage 2025 Population Estimates (county population) and 2025 Gazetteer Files (land area and interior point of each ZIP code). Public domain.
  • U.S. Census Bureau, Cartographic Boundary Files: ZCTAs 2020 and counties 2025, 1:500,000; county adjacency file 2025. Public domain.

How we count. ZIP codes here are the Census Bureau’s ZIP Code Tabulation Areas (ZCTAs), the areas it draws to match USPS ZIP codes; ZIPs with no area of their own (PO boxes, single buildings) aren’t included. A ZIP can cross county lines: “Land in the county” is the exact share of its land inside, from the Census relationship files. “Residents in the county” is the whole ZIP for those entirely inside; for shared ones it’s an estimate, spreading the people of each census tract over the land it shares with the ZIP. Population: ACS 2020–2024. Methodology.

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