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

ZIP stands for Zone Improvement Plan. The codes went live on July 1, 1963.The lowest ZIP code is 00501 — the IRS in Holtsville, New York.The highest ZIP code is 99950, in Ketchikan, Alaska.Type 07734 into a calculator and turn it upside down: hELLO. It is Keansburg, New Jersey.12345 belongs to one company: General Electric in Schenectady, New York.The first digit is a region: 0 is New England and New Jersey, 9 is the West Coast, Alaska and Hawaii.Mr. ZIP, the cartoon mailman, was the mascot that sold the idea to America.ZIP+4 arrived in 1983 and can narrow a ZIP down to one side of one block.A ZIP code is a mail route, not a place: plenty of them cross county and even state lines.Play ZIP Hunt: guess the secret ZIP code of the day in six tries.
zipcodes.pro — STATE/OH/COUNTY/HARDIN

Hardin County, OH ZIP codes

There are 10 ZIP codes in Hardin County, OH, in 10 towns, from 43310 to 45859. The largest are 43326 (Kenton), 45810 (Ada) and 45843 (Forest).

The county seat is Kenton.

ZIP codes
10
Towns
10
County seat
Kenton
County FIPS
39065
State
Ohio
Population
30,475
Median household income
$62,484
Land area
470 sq mi

Hardin County ZIP codes by town

Kenton (county seat)
43326

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 Hardin County ZIP codes

43310433264334043346458104581245835458364584345859

The ZIP codes of Hardin 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.

Hardin County in numbers

About 30,475 people live in Hardin County, in 11,724 households, the 72nd most populous of Ohio's 88 counties. The median household income is $62,484 a year, 12% below the Ohio median of $71,389 (US: $80,734). The median owner-occupied home is valued at $151,200 (30% below the Ohio median), and median gross rent is $793 a month. The median age is 35.2; 19.5% of adults 25 and over hold a bachelor's degree or higher (31.5% across Ohio); the average commute takes 24 minutes.

Population30,475Hardin30,475
Households11,724Hardin11,724
Median age35.2Hardin35.2Ohio39.7US 38.9
Median household income$62,484Hardin$62,484Ohio$71,389US $80,734
Median home value$151,200Hardin$151,200Ohio$214,800US $332,700
Median gross rent$793Hardin$793Ohio$1,034US $1,413
Bachelor's degree or higher19.5%Hardin19.5%Ohio31.5%US 35.7%
Mean commute23.6 minHardin23.6 minOhio23.4 minUS 26.4 min
Population density65 / sq miHardin65 / 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 Hardin County

Largest towns in Hardin County
TownZIP codesPopulation
Kenton 1 7,663
Ada 1 4,797
Forest 1 1,286
Dunkirk 1 839
Belle Center 1 770
Alger 1 718
Mount Victory 1 577
Mc Guffey 1 384
Roundhead 1 238
Dola 1 126

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 Hardin County.

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

Every ZIP code in Hardin County, with figures

ZIP codes in Hardin County
ZIP City Type Population Median income Median home
43310 Belle Center , OH Standard 3,177 $68,388 $163,300
43326 Kenton , OH Standard 12,573 $63,785 $153,200
43340 Mount Victory , OH Standard 2,103 $72,446 $192,900
43346 Roundhead , OH Standard 238 $57,130 —
45810 Ada , OH Standard 7,449 $63,451 $167,900
45812 Alger , OH Standard 2,027 $44,045 $137,100
45835 Dola , OH Standard 449 $76,042 $97,900
45836 Dunkirk , OH Standard 1,573 $56,250 $119,700
45843 Forest , OH Standard 4,184 $71,541 $176,200
45859 Mc Guffey , OH Standard 384 $51,250 $77,900

Cite this page

zipcodes.pro. “Hardin County ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/state/oh/county/hardin

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