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/KY/COUNTY/OHIO

Ohio County, KY ZIP codes

There are 12 ZIP codes in Ohio County, KY, in 12 towns, from 42320 to 42378. The largest are 42320 (Beaver Dam), 42347 (Hartford) and 42378 (Whitesville).

The county seat is Hartford.

ZIP codes
12
Towns
12
County seat
Hartford
County FIPS
21183
Population
23,735
Median household income
$57,798
Land area
587 sq mi

Ohio County ZIP codes by town

Hartford (county seat)
42347

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 Ohio County ZIP codes

423204232842333423384234342347423494235442361423694237042378

The ZIP codes of Ohio 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.

Ohio County in numbers

About 23,735 people live in Ohio County, in 9,107 households, the 49th most populous of Kentucky's 120 counties. The median household income is $57,798 a year, 9% below the Kentucky median of $63,726 (US: $80,734). The median owner-occupied home is valued at $121,400 (41% below the Kentucky median), and median gross rent is $739 a month. The median age is 40.5; 13.9% of adults 25 and over hold a bachelor's degree or higher (27.6% across Kentucky); the average commute takes 28 minutes.

Population23,735Ohio23,735
Households9,107Ohio9,107
Median age40.5Ohio40.5Kentucky39.1US 38.9
Median household income$57,798Ohio$57,798Kentucky$63,726US $80,734
Median home value$121,400Ohio$121,400Kentucky$205,600US $332,700
Median gross rent$739Ohio$739Kentucky$967US $1,413
Bachelor's degree or higher13.9%Ohio13.9%Kentucky27.6%US 35.7%
Mean commute28.1 minOhio28.1 minKentucky24.0 minUS 26.4 min
Population density40 / sq miOhio40 / 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 Ohio County

Largest towns in Ohio County
TownZIP codesPopulation
Beaver Dam 1 3,524
Hartford 1 2,649
Horse Branch 1 1,962
Whitesville 1 661
Cromwell 1 644
Fordsville 1 453
Olaton 1 425
Centertown 1 371
Mc Henry 1 283
Rockport 1 233
Rosine 1 76
Dundee 1 12

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 Ohio County.

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

Every ZIP code in Ohio County, with figures

ZIP codes in Ohio County
ZIP City Type Population Median income Median home
42320 Beaver Dam , KY Standard 9,128 $54,730 $150,200
42328 Centertown , KY Standard 1,158 $57,679 $97,200
42333 Cromwell , KY Standard 644 $33,969 $85,000
42338 Dundee , KY Standard 12 — —
42343 Fordsville , KY Standard 1,267 $52,679 $86,700
42347 Hartford , KY Standard 5,829 $60,900 $134,500
42349 Horse Branch , KY Standard 1,962 $58,601 $88,900
42354 Mc Henry , KY Standard 283 $65,625 $102,100
42361 Olaton , KY Standard 425 $43,750 $89,100
42369 Rockport , KY Standard 223 $62,750 $77,300
42370 Rosine , KY Standard 16 — —
42378 Whitesville , KY Standard 3,513 $73,419 $181,400

Cite this page

zipcodes.pro. “Ohio County ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/state/ky/county/ohio

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