Every ZIP code in the United States, with weather, radar, trivia and the numbers behind it. Five digits since 1963!

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zipcodes.pro — STATE/NJ/COUNTY/MERCER

Mercer County, NJ ZIP codes

There are 39 ZIP codes in Mercer County, NJ, in 9 towns, from 08520 to 08695. The largest are 08540 (Princeton), 08610 (Trenton) and 08618 (Trenton).

The county seat is Trenton.

ZIP codes
39
Towns
9
County seat
Trenton
County FIPS
34021
Population
385,864
Median household income
$100,645
Land area
224 sq mi
Area codes
609, 640

Mercer County ZIP codes by town

Each ZIP code is listed under the county most of its land lies in and the town the Postal Service names it for; a ZIP code's own page shows exactly how it is split.

Map of Mercer County ZIP codes

085200852508534085400854108542085430854408550085600856108601086020860308604086050860608607086080860908610086110861808619086200862508628086290863808644086450864608647086480865008666086900869108695

The ZIP codes of Mercer County, shaded. Outlines are Census ZIP Code Tabulation Areas (2020), which approximate the mail routes; PO-box and single-address codes have no area and are not drawn. Click any area to open its ZIP code.

Mercer County in numbers

About 385,864 people live in Mercer County, in 144,114 households, the 12th most populous of New Jersey's 21 counties. The median household income is $100,645 a year, about the same as the New Jersey median of $103,556 (US: $80,734). The median owner-occupied home is valued at $377,700 (17% below the New Jersey median), and median gross rent is $1,623 a month. The median age is 39.5; 45.4% of adults 25 and over hold a bachelor's degree or higher (43.6% across New Jersey); the average commute takes 27 minutes.

Population385,864Mercer385,864
Households144,114Mercer144,114
Median age39.5Mercer39.5New Jersey40.1US 38.9
Median household income$100,645Mercer$100,645New Jersey$103,556US $80,734
Median home value$377,700Mercer$377,700New Jersey$454,400US $332,700
Median gross rent$1,623Mercer$1,623New Jersey$1,720US $1,413
Bachelor's degree or higher45.4%Mercer45.4%New Jersey43.6%US 35.7%
Mean commute27.1 minMercer27.1 minNew Jersey30.5 minUS 26.4 min
Population density1,719 / sq miMercer1,719 / sq mi

U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates. Survey estimates carry margins of error, wider for small places. Sources and methods.

Largest towns in Mercer County

Largest towns in Mercer County
TownZIP codesPopulation
Trenton 27 90,338
Lawrence Township 1 31,323
Princeton 5 30,756
Hightstown 1 5,920
Pennington 1 2,827
Princeton Junction 1 2,025
Hopewell 1 1,823
Titusville 1 501
Windsor 1 325

Population of the census place of that name where there is one, otherwise of the ZIP codes the Postal Service addresses by it. A town's ZIP codes can reach past the county line.

Neighbouring counties

Counties that share a ZIP code with Mercer County.

Not sure you are in Mercer County? What county am I in? answers from your location, near a county line included.

Every ZIP code in Mercer County, with figures

ZIP codes in Mercer County
ZIP City Type Population Median income Median home
08520 Hightstown , NJ Standard 29,504 $118,010 $376,600
08525 Hopewell , NJ Standard 4,522 $165,324 $572,500
08534 Pennington , NJ Standard 13,272 $175,573 $573,000
08540 Princeton , NJ Standard 50,388 $176,983 $767,900
08541 Princeton , NJ No street area — — —
08542 Princeton , NJ Standard 2,533 $105,524 $754,100
08543 Princeton , NJ No street area — — —
08544 Princeton , NJ Standard 4,392 — —
08550 Princeton Junction , NJ Standard 21,067 $224,213 $807,200
08560 Titusville , NJ Standard 3,245 $128,516 $420,300
08561 Windsor , NJ Standard 325 — $484,400
08601 Trenton , NJ No street area — — —
08602 Trenton , NJ No street area — — —
08603 Trenton , NJ No street area — — —
08604 Trenton , NJ No street area — — —
08605 Trenton , NJ No street area — — —
08606 Trenton , NJ No street area — — —
08607 Trenton , NJ No street area — — —
08608 Trenton , NJ Standard 1,250 $61,201 $132,400
08609 Trenton , NJ Standard 15,938 $68,238 $103,700
08610 Trenton , NJ Standard 33,465 $83,906 $264,600
08611 Trenton , NJ Standard 31,995 $56,788 $160,500
08618 Trenton , NJ Standard 35,634 $50,390 $227,000
08619 Trenton , NJ Standard 24,089 $105,946 $352,500
08620 Trenton , NJ Standard 11,621 $105,368 $373,800
08625 Trenton , NJ No street area — — —
08628 Trenton , NJ Standard 9,831 $108,158 $369,500
08629 Trenton , NJ Standard 13,013 $82,646 $182,400
08638 Trenton , NJ Standard 22,816 $66,875 $245,100
08644 Trenton , NJ No street area — — —
08645 Trenton , NJ No street area — — —
08646 Trenton , NJ No street area — — —
08647 Trenton , NJ No street area — — —
08648 Lawrence Township , NJ Standard 31,323 $125,514 $428,000
08650 Trenton , NJ No street area — — —
08666 Trenton , NJ No street area — — —
08690 Trenton , NJ Standard 18,841 $127,339 $383,900
08691 Trenton , NJ Standard 16,607 $132,520 $552,000
08695 Trenton , NJ No street area — — —

Cite this page

zipcodes.pro. “Mercer County ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/state/nj/county/mercer

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