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/NC/COUNTY/JOHNSTON

Johnston County, NC ZIP codes

There are 11 ZIP codes in Johnston County, NC, in 10 towns, from 27504 to 27593. The largest are 27520 (Clayton), 27527 (Clayton) and 27577 (Smithfield).

The county seat is Smithfield.

ZIP codes
11
Towns
10
County seat
Smithfield
County FIPS
37101
Population
234,263
Median household income
$83,384
Land area
792 sq mi
Area codes
919, 984
Metro area
Raleigh-Cary

Johnston County ZIP codes by town

Smithfield (county seat)
27577

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 Johnston County ZIP codes

2750427520275242752727542275552756827569275762757727593

The ZIP codes of Johnston 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.

Johnston County in numbers

About 234,263 people live in Johnston County, in 85,591 households, the 12th most populous of North Carolina's 100 counties. The median household income is $83,384 a year, 15% above the North Carolina median of $72,388 (US: $80,734). The median owner-occupied home is valued at $305,600 (6% above the North Carolina median), and median gross rent is $1,146 a month. The median age is 38.1; 28.9% of adults 25 and over hold a bachelor's degree or higher (35.7% across North Carolina); the average commute takes 32 minutes.

Population234,263Johnston234,263
Households85,591Johnston85,591
Median age38.1Johnston38.1North Carolina39.1US 38.9
Median household income$83,384Johnston$83,384North Carolina$72,388US $80,734
Median home value$305,600Johnston$305,600North Carolina$288,900US $332,700
Median gross rent$1,146Johnston$1,146North Carolina$1,228US $1,413
Bachelor's degree or higher28.9%Johnston28.9%North Carolina35.7%US 35.7%
Mean commute32.2 minJohnston32.2 minNorth Carolina25.1 minUS 26.4 min
Population density296 / sq miJohnston296 / 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 Johnston County

Largest towns in Johnston County
TownZIP codesPopulation
Clayton 2 29,320
Smithfield 1 12,116
Selma 1 6,817
Benson 1 4,282
Four Oaks 1 2,459
Kenly 1 2,359
Pine Level 1 2,031
Princeton 1 1,658
Micro 1 573

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 Johnston County.

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

Every ZIP code in Johnston County, with figures

ZIP codes in Johnston County
ZIP City Type Population Median income Median home
27504 Benson , NC Standard 17,079 $66,724 $245,600
27520 Clayton , NC Standard 48,014 $86,322 $320,900
27524 Four Oaks , NC Standard 13,999 $75,827 $212,500
27527 Clayton , NC Standard 39,256 $115,035 $390,200
27542 Kenly , NC Standard 9,850 $66,038 $214,100
27555 Micro , NC Standard 573 $44,531 $170,700
27568 Pine Level , NC Standard 1,542 $66,071 $230,800
27569 Princeton , NC Standard 8,833 $78,850 $221,700
27576 Selma , NC Standard 21,624 $66,831 $207,600
27577 Smithfield , NC Standard 28,354 $62,758 $260,300
27593 Wilsons Mills , NC Standard 0 — —

Cite this page

zipcodes.pro. “Johnston County ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/state/nc/county/johnston

Underlying data is public domain or openly licensed — sources, vintages and licences.